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Full text of "A management plan for agricultural subsurface drainage and related problems on the westside San Joaquin Valley : final report of the San Joaquin Valley Drainage Program"

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A Management Plan 

For Agricultural Subsurface Drainage 

and Related Problenns on the 

Westside San Joaquin Valley 

September 1990 




A Management Plan 

for 

Agricultural Subsurface Drainage 

and Related Problems on the Westside 

San Joaquin Valley 



Final Report 

of the 
San Joaquin Valley Drainage Program 

September 1990 



U.S. DEPARTMENT OF THE INTERIOR 
Bureau of Reclamation 
Fish and Wildlife Service 
Geological Survey 



CALIFORNIA RESOURCES AGENCY 

Department of Fish and Game 

Department of Water Resources 



PREFACE 



A comprehensive study of agricultural drainage and drainage-related problems on the 
westside San Joaquin Valley has resulted in the management plan presented in this final 
report of the Federal-State interagency San Joaquin Valley Drainage Program. 

Understandably, some may be disappointed that no single, sure, and lasting solution to the 
drainage problem has been put forward. Rather, the management plan presented is complex 
and includes risks that could be costly. Moreover, it may be only the first step in solving the 
salt accumulation problem. Virtually everyone involved in examination of the drainage 
problem agrees, however, that there is no single solution and no easy answer to the problem. 

But it is also generally agreed that the drainage problem is manageable and that this 
management logically begins in the valley with a broadly shared effort to reduce the amount 
of drainage water, to place the remaining water under control, and to contain and isolate 
toxicants such as selenium. Such actions would largely correct present problems of 
waterlogging of farmlands and could greatly reduce adverse impacts on fish and wildlife. 

The in-valley actions recommended in the plan would also be necessary for any eventual 
export of salt from the San Joaquin Valley. The recommended actions would provide a 
regional drainage infrastructure that now exists only in scattered pieces. If the plan proposed 
here is implemented, a salt export decision need not be made for several decades. 

A review of the history of the drainage problem suggests that some of the reasons the 
problem has grown to nearly 500,000 acres and is adversely affecting the environment include: 
(1) Continued hopes for a master drain, (2) expectations of a technological breakthrough in 
drainage water treatment, (3) the need for more information, and (4) a lack of cooperation 
among parties affected. Viewed as an accumulation of years of piecemeal efforts and neglect, 
the problem appears overwhelming. It is not. Systematic, shared work begun now can 
manage the problem and contribute to its eventual solution. 



^ Xn4^ 



Edgar A. Imhoff, Program Manager 
San Joaquin Valley Drainage Program 



ui 



CONTENTS 



Preface iii 

San Joaquin Valley Drainage Program Committee and Team Membership xi 

Chapter 1. SUMMARY OF THE PLAN AND RECOMMENDATIONS FOR ACTION ... 1 

Summary of the Plan 1 

Conclusions and Recommendations for Action 6 

Implementation 6 

Planning 9 

Monitoring 10 

Additional Study 11 

Drainage Management 11 

Geohydrology 11 

Economics 12 

Fish and Wildlife 12 

Public Health 13 

Funding Proposed Actions 13 

Chapter 2. THE PROBLEM 15 

A Brief History 15 

The Area of Concern 18 

Interests Affected by Drainage Problems 20 

Agriculture 20 

Fish and Wildlife 21 

Water Quality 21 

Public Health 23 

Chapter 3. WHAT THE STUDY HAS REVEALED OR CONFIRMED 25 

Geohydrology 25 

Geology 25 

Surface Water 27 

Ground Water 29 

Drainage-Water Constituents 30 

Salinity 30 

Trace Elements 39 

Drainage-Water Treatment and Reuse 42 

Treatment Processes 42 

Anaerobic-Bacterial Process 43 



V - 



Chapter 3. WHAT THE STUDY HAS REVEALED OR CONFIRMED (continued) 

Facultative-Bacterial Process 44 

Microalgal-Bacterial Process 45 

Microbial Volatilization of Selenium in Evaporation Pond Water 45 

Microbial Volatilization of Selenium from Soils and Sediments 45 

Geochemical Immobilization 46 

Iron Filings 47 

Ferrous Hydroxide 47 

Ion Exchange 48 

Reverse Osmosis to Remove Salts and Contaminants 48 

Cogeneration 48 

Future of Treatment Processes 48 

Reuse 49 

Agricultural Economy 50 

The Contribution of Agriculture 50 

Exports 51 

Land Use 52 

Production Expenses 53 

Farm Structure 54 

Federal Agricultural Programs 55 

Fish and Wildlife Resources 56 

Habitat Losses and Population Declines 56 

Water Supplies and Needs 57 

Toxicity of Drainage-Water Contaminants 58 

Contamination and Biological Effects 59 

Agroforestry Plantations 60 

Public Health 60 

Safety of Food Crops 60 

Safety of Consuming Fish and Game 61 

Safety of Foraging 62 

Occupational Exposures to Drainage Contaminants 62 

Safety of Drinking Water 63 

Social Conditions 63 

Community Infrastructure 63 

Farm Labor 63 

Water Supply and Drainage Management Organizations 64 

Water Management Networks 64 

Regional Institutional Spheres 65 

The Existing Institutional Structure 65 



- VI 



Chapter 4. THE PLANNING FRAMEWORK 69 

Public Policy 69 

Drainage Service 69 

Environmental Protection 70 

Drainage Studies and Monitoring 70 

Constraints 71 

Local Drainage Management Initiatives 71 

Planning Objectives 72 

Program Planning Methods 72 

Estimating the Volume of Water Causing Drainage Problems 75 

Chapter 5. IN-VALLEY MANAGEMENT OPTIONS AND PLANNING ALTERNATIVES 79 

The Future -Without Alternative 79 

The Overall Theme 79 

Assumptions About the Future 80 

The Shape of the Future Under the Future-Without Alternative 81 

Land-Use Change 81 

Hydrologic Effects 82 

Economic Effects 83 

Effects on Fish and Wildlife Resources 85 

Public Health Effects 86 

Social Effects 86 

Options for Drainage- Water Management 87 

Drainage-Water Source Control 87 

Ground-Water Management 88 

Drainage- Water Treatment 88 

Drainage-Water Reuse 90 

Drainage-Water Disposal 90 

Fish and Wildlife Measures 90 

Institutional Changes 91 

Evaluation of Options 92 

Planning Alternatives 98 

Drainage Management Strategies Underlying the Alternatives 98 

Source Control 98 

Drainage-Water Reuse 99 

Ground-Water Management 102 

Land Retirement 103 

Description of Alternatives 106 

Northern Subarea 106 

Grasslands Subarea 107 

Westlands Subarea 110 

Tulare Subarea 113 

Kern Subarea 113 

Summary and Conclusions from Analyses of Subarea Planning Alternatives 118 



- vn 



Chapter 6. THE RECOMMENDED PLAN 121 

Plan Formulation Procedure 121 

Land Retirement Decisions 121 

Source Control Decisions 121 

Decisions on Discharge to the San Joaquin River 126 

Reuse Decisions 126 

Evaporation Pond Decisions 127 

Treatment for Selenium Removal 127 

Ground-Water Pumping Decisions 127 

Rationale on Salt Balance 127 

Plan Features Common to All Subareas 129 

Drainage- Water Source Control 129 

Reduction of Drainage-Water Volume by Reuse 131 

Disposal of Concentrated Drainage Water 132 

Institutional Components 132 

Tiered Water Pricing 132 

Improved Scheduling of Water Deliveries 132 

Water Transfers and Marketing 133 

Regional Drainage Management Organizations 133 

Monitoring of the Drainage-Water Environment 133 

Description and Evaluation of the Recommended Plan 134 

Northern Subarea 134 

Grasslands Subarea 136 

Assessment of Plan Features and Their Effects 141 

Westlands Subarea 144 

Assessment of Plan Features and Their Effects 147 

Tulare Subarea 149 

Assessment of Plan Features and Their Effects 152 

Kern Subarea 153 

Assessment of Plan Features and Their Effects 156 

Evaluation of Plan and Comparison to Future-Without 158 

References Cited 163 

Selected Bibliography 169 

Abbreviations 177 

Glossary 179 

TABLES 

1 Summary of Recommended Drainage Management Plan 3 

2 Problem Water Reduction, 2040 4 

3 Annualized Costs of the Recommended Plan 5 

4 Substances of Concern 40 

5 Status of Drainage-Water Treatment Processes to Remove 

or Immobilize Selenium 44 

6 Public Health Concerns Associated with Drainage Water 62 

7 Planning Objectives, Criteria, and Standards 73 



- viu - 



TABLES (continued) 

8 Forecast of Irrigated Area With Water T^ble Less Than 5 Feet from Ground Surface 76 

9 Forecasts of Extent of Drainage Problem Area 76 

10 Estimate of Annual Problem Water Volume 77 

11 Irrigated Land Changes Under the Future-Without Alternative 81 

12 Change in Irrigable Area and Water Requirement Under the Future-Without Alternative 83 

13 Estimated Subsurface Drainage Volume Under the Future-Without Alternative 83 

14 Reduction in Retail Sales, Income, and Employment from Present to 

Future-Without Conditions, 1987-2040 84 

15 Applicability of Drainage Management Options: Level "A" Performance Standards 93 

16 Applicability of Drainage Management Options: Level "B" Performance Standards 94 

17 Summary Evaluation of Options Considered for Drainage Management Alternatives 95 

18 Major Features of Grasslands Subarea Planning Alternatives 109 

19 Major Features of Westlands Subarea Planning Alternatives 112 

20 Major Features of Tblare Subarea Planning Alternatives 115 

21 Major Features of Kern Subarea Planning Alternatives 117 

22 Major Features of Study Area Planning Alternatives 119 

23 Performance Standards Used to Formulate Recommended Plan 122 

24 Applicability of Drainage Management Options 123 

25 Estimated Useful Life of the Semiconfined Aquifer 129 

26 Recommended Targets for Reduction in Deep Percolation in 2000 130 

27 Projected On-Farm Tile Drainage Acreage 131 

28 Primary Drainage- Water Reduction Facilities 132 

29 Recommended Drainage Management Plan, Grasslands Subarea 138 

30 Comparison of Plan With Present and Future-Without Conditions, Grasslands Subarea 142 

31 Annualized Costs of the Recommended Plan for the Grasslands Subarea 143 

32 Recommended Drainage Management Plan, Westlands Subarea 146 

33 Comparison of Plan With Present and Future-Without Conditions, Westlands Subarea 147 

34 Annualized Costs of the Recommended Plan for the Westlands Subarea 148 

35 Recommended Drainage Management Plan, Tulare Subarea 151 

36 Comparison of Plan With Present and Future-Without Conditions, Tlilare Subarea 152 

37 Annualized Costs of the Recommended Plan for the TUlare Subarea 153 

38 Recommended Drainage Management Plan, Kern Subarea 155 

39 Comparison of Plan With Present and Future-Without Conditions, Kern Subarea 157 

40 Annualized Costs of the Recommended Plan for the Kern Subarea 157 

41 Water Potentially Available Through Recommended Plan Actions 158 

42 Summary of Annual Water Needs for Fish Protection, Substitute Water Supply for 

Wildlife Areas, and Alternative Habitat for Evaporation Ponds 159 

43 Area of Evaporation and Solar Ponds and Wetlands in the Recommended Plan 159 

44 Comparison of Selected Water Features and Effects of the Recommended 

Plan and Future-Without Conditions, 2040 160 

45 Comparison of Selected Land Features and Effects of the Recommended 

Plan and Future-Without Conditions, 2040 160 

46 Increase in Retail Sales, Income, and Employment from Future-Without 

Conditions to the Recommended Plan for Selected Subareas, 2040 161 



- IX - 



FIGURES 

1 Program Study Area 2 

2 Major Federal and State Irrigation Facilities and Service Areas 19 

3 Major Public Wildlife Areas in the San Joaquin Valley 22 

4 Generalized Geohydrological Cross-Sections in the San Joaquin and TUlare Basins 26 

5 Selenium Concentrations in Soils 28 

6 Areas of Shallow Ground Water, 1987 31 

7 Salinity in Shallow Ground Water Sampled Between 1984 and 1989 32 

8 Selenium Concentrations in Shallow Ground Water Sampled Between 1984 and 1989 33 

9 Boron Concentrations in Shallow Ground Water Sampled Between 1984 and 1989 34 

10 Molybdenum Concentrations in Shallow Ground Water Sampled 

Between 1984 and 1989 35 

11 Arsenic Concentrations in Shallow Ground Water Sampled Between 1984 and 1989 36 

12 Aquifer Zones Above the Corcoran Clay With Less Than 

1,250 ppm Total Dissolved Solids 37 

13 San Joaquin Valley Total Crop Production Value 50 

14 Agriculturally Induced Employment in the San Joaquin Valley by County, 1987 51 

15 Share of California Commodity Exports, by Value, 1987 52 

16 Irrigated Cropland in Cotton, Fruits, and Nuts, by Subarea - 1987 54 

17 Percent of Farms by Tenure of Operator, Westside San Joaquin Valley, 1987 55 

18 Shallow Ground-Water Quality Zones 78 

19 The Concept of Drainage-Water Reuse 100 

20 Pond Configurations 101 

21 The Concept of Ground-Water Management 102 

22 The Concept of Land Retirement 104 

23 Areas of Highest Observed Selenium Concentrations in Shallow Ground Water 105 

24 Problem Water Reduction, Grasslands Subarea 108 

25 Problem Water Reduction, Westlands Subarea Ill 

26 Problem Water Reduction, Tulare Subarea 114 

27 Problem Water Reduction, Kern Subarea 1 16 

28 Overall Plan Formulation Sequence 124 

29 Plan Formulation Sequence: Pump Semiconfined Aquifer 125 

30 Plan Formulation Sequence: Evaporate Drainage 125 

3 1 Northern Subarea 135 

32 Grasslands Subarea, Ground-Water Quality Zones 137 

33 Facilities and Flows Included in the Recommended Plan, Grasslands Subarea 140 

34 Westlands Subarea, Ground-Water Quality Zones 145 

35 Tulare Subarea, Ground-Water Quality Zones 150 

36 Kern Subarea, Ground- Water Quality Zones 154 



- X - 



SAN JOAQUIN VALLEY DRAINAGE PROGRAM 
COMMITTEE AND TEAM MEMBERSHIP 



The San Joaquin Valley Drainage Program is a Federal/State interagency program that was established in 
August 1984 by then Secretary of the Interior William Clark and California Governor George Deukmejian. 



INTERGOVERNMENTAL COORDINATION TEAM 



Peter Bontadelli, CA Department of Fish and Game 
Constance Harriman, US Department of the Interior 
David Kennedy, CA Department of Water Resources 
W Don Maughan, CA State Water Resources Control Board 
Dallas Peck, US Geological Survey 



John Sayre, US Department of the Interior 
Jananne Sharpless, CA Environmental Affairs 

Agency 
John Turner, US Fish and Wildlife Service 
Dennis Underwood, US Bureau of Reclamation 



Gordon Van Vleck, CA Resources Agency 



POLICY AND MANAGEMENT COMMITTEE 



Peter Bontadelli, CA Department of Fish and Game 

H. K. (Pete) Chadwick (alternate) 

Lawrence Hancock, US Bureau of Reclamation 

Dan Fults (alternate) 

David Kennedy, CA Department of Water Resources 



Louis Beck (alternate) 

John Klein, US Geological Survey 

Robert Gillion (alternate) 

Marvin Plenert, US Fish and Wildlife Service 

Wayne White (alternate) 



CITIZENS ADVISORY COMMITTEE 



Donald Anthrop, San Jose State University 

Jean Auer, Committee for Water Policy Consensus 

Jerald Butchert, Westlands Water District 

James Crenshaw, CA Sportfishing Protection Alliance 

Michael DiBartolomeis, Toxicology Research International 

Thomas Graff, Environmental Defense Fund 

Stephen Hall, Land Preservation Association 

Clifford Koster, Water Committee for San Joaquin Farm Bureau 



Chester McCorkle, University of California, 

Davis 
Daniel Nelson, San Luis Water District 
Polly Smith, CA Lxague of Women Voters 
Michael Steams, Irrigation and Canal Districts 

Coalition in Fresno and Merced Counties 
Ronald Stork, Friends of the River. Sierra Club 
Joseph Summers, Summers Engineering, Inc. 



INTERAGENCY TECHNICAL ADVISORY COMMITTEE 



Mohammed Alemi, State Water Resources Control Board 
Suzanne Butterfield, CA Department of Water Resources 
Harley Davis, Central Valley Regional Water Quality 

Control Board 
Richard Haberman, CA Department of Health Services 
Henry Hansen. US Bureau of Reclamation 
Susan Klasing, consultant 



Karl Longley, California State University, Fresno 
Stephen Moore, US Fish and Wildlife Service 
Larry Puckett, CA Department of Fish and Game 
Maria Rea, US Environmental Protection Agency 
Walter Sykes. US Department of Agriculture 
Marc Sylvester. US Geological Survey 
Kenneth Tanji, University of California, Davis 



ITAC Subcommittee on Agricultural Water Management 



James Ayars, California State University. Fresno 

Ken Billings, Federal Land Bank 

Suzanne Butterfield, CA Department of Water Resources 

Charies Burt, Cal Poly San Luis Obispo 

Jerald Butchert. Westlands Water District 

William Camp. Firebaugh Canal Company 

Baryohay Davidoff. CA Department of Water Resources 

Dennis Falaschi. Panoche Water District 

Stephen Hall, Land Preservation Association 

Blaine Hansen, University of California, Davis 

Richard Howitt. University of California. Davis 

Elizabeth Hudson. Westlands Water District 

David Woolley, 



Dale Melville, Provost and Pritchard and Dudley 

Ridge Water District 
Daniel Nelson, San Luis Water District 
James Oster, University of California, Riverside 
Claude Phene, US Department of Agriculture 
Michael Porter, Central California Irrigation District 
Nigel Quinn, San Joaquin Valley Drainage Program 
Kenneth Solomon, CA State University, Fresno 
Kenneth Tanji, University of California, Davis 
Wesley Wallender, University of California, Davis 
Dennis Westcot, CV Reg. Water Quality Control Bd. 
Zachary Willey, Environmental Defense Fund 
Murrieta Farms 



XI 



ITAC Subcommittee on Aquatic and Fisheries Biology 

James Arthur. US Bureau of Reclamation Peter Moyle, University of California, Davis 

Randall Brown. CA Department of Water Resources Larry Puckett, CA Department of Fish and Game 

Francisco Demgen, Aquatic Habitat Institute Maria Rea. US Environmental Protection Agency 

Perry Herrgesell, CA Department of Fish and Game Bert Tribbey. California State University, Fresno 

Martin Kjelson, US Fish and Wildlife Service Terry Young, Environmental Defense Fund 

ITAC Subcommittee on Data Management 

Sheryl Baughman. US Bureau of Reclamation Charles Johnson. US Bureau of Reclamation 

Randall Brown. CA Department of Water Resources Martin Kjelson. US Fish and Wildlife Service 

Bellory Fong. CA Department of Water Resources Larry Ludke, US Fish and Wildlife Service 

Steven Grattan, University of California, Davis James Sutton. CA State Water Resources Control 
Frederick Heimes. US Geological Survey Board 

Perry Herrgesell. CA Department of Fish and Game Walter Swain, US Geological Survey 

Gail Thclin, US Geological Survey 

ITAC Subcommittee on Ground Water 

James Ayars. USDA Agricultural Research Service William Lettis. consultant 

Vashek Cervinka. US Department of Food and Agriculture Karl lx)ngley, California State University. Fresno 

Michael Day. J. M. Lord. Inc. William (BJ) Miller, consultant 

Steven Dcverel. US Geological Survey William Pipes, consultant 

Neil Dubrovsky. US Geological Survey Nigel Quinn. San Joaquin Valley Drainage Program 

Terry Ericwine. CA Department of Water Resources Kenneth Schmidt, consultant 

Terence Garvey, Westlands Water District Walter Swain, San Joaquin Valley Drainage 

Mark Grismer. University of California, Davis Program 

Blaine Hansen, University of California, Davis Arvey Swanson, CA Department of Water 

Lance Johnson, Westlands Water District Resources 

Howard Weinberg. CA State Water Resources Control Board 

ITAC Subcommittee on Public Health 

Bruce Eldridge, University of California, Davis Michael MacLean, Tulare County Department of 

Anna Fan. CA Department of Health Services Health Services 

Richard Jacobs. US Food and Drug Administration Raymond Neutra. CA Department of Health 

Susan Klasing. consultant Services 

Karl Lx)ngley. CA State University. Fresno Jane Valentine. University of California. Ixis Angeles 

Richard Welch, Merced County Health Department 

ITAC Subcommittee on Treatment and Disposal 

Mohammed Alemi. CA State Water Resources Control Board Richard Hansen, CA Department of Fish and Game 

Paulette Altringer. US Bureau of Mines Robin Hewitt. US Environmental Protection Agency 

Randall Brown, CA Department of Water Resources George Nishimura, San Joaquin Valley Drain. Prog. 

Roger Fujii, US Geological Survey James Rhoades, USDA-ARS Salinity Laboratory 

Terence Garvey, Westlands Water District Theodore Roefs. US Bureau of Reclamation 

Richard Haberman. CA Department of Health Services Brian Smith. CA Department of Water Resources 

Felix Smith, US Fish and Wildlife Service 

ITAC Subcommittee on Valley Biology 

Dick Daniel. CA Department of Fish and Game David Pelgen, CA Department of Water Resources 

John Fields. US Bureau of Reclamation Maria Rea, US Environmental Protection Agency 

Allan Knight, University of California. Davis Maurice Taylor, US Fish and Wildlife Service 



Xll 



NATIONAL RESEARCH COUNCIL - WATER SCIENCE AND TECHNOLOGY BOARD 
COMMITTEE ON IRRIGATION-INDUCED WATER QUALITY PROBLEMS 



Ernest Angino, University of Kansas, Lawrence 
Margriet Caswell. University of California, Santa Barbara 
Edwin Clark. II, Department of Natural Resources and 

Environmental Control, State of Delaware 
Charles DuMars, University of New Mexico, Albuquerque 
Chris Elfring, NRC Staff Officer 
Wilford Gardner, University of California, Berkeley 
Rolf Hartung, University of Michigan, Ann Arbor 
Charles Howard, Charles Howard and Associates, Ltd. 



L. Douglas James, Utah State University, Logan 
William Lewis, Jr., University of Colorado, Boulder 
Robert Meglen, University of Colorado, Denver 
Ishwar Murarka, Electric Power Research Institute 
Albert Page, University of California, Riverside 
Merilyn Reeves, League of Women Voters 
Daniel Willard, Indiana University, Bloomington 
Jan van Schilfgaarde, USDA Agricultural Research 
Service 



CIIWQP Subcommittee on Data Management 



Margriet Caswell, University of CA, Santa Barbara 
Edwin Clark, II, Department of Natural Resources 
and Environmental Control, State of Delaware 



Wilford Gardner, University of California, Berkeley 
Robert Meglen, University of Colorado, Denver 



CIIWQP Subcommittee on Economics, Policy, and Systems Analysis 



Margriet Caswell. University of California, Santa Barbara 
Edwin Clark, II, Department of Natural Resources and 

Environmental Control, State of Delaware 
Charles DuMars, University of New Mexico, Albuquerque 
Wilford Gardner, University of California, Berkeley 
Frank Gregg, University of Arizona, Tucson 



Evan Vlachos, Colorado State University, Fort Collins 



Charles Howard, Charles Howard & Associates, Ltd. 
Charles Howe, University of Colorado, Boulder 
Gerald Orlob, University of California, Davis 
Albert Page, University of California, Riverside 
Merilyn Reeves, League of Women Voters 
Warren Viessman, University of Florida, Gainesville 



CIIWQP Subcommittee on Public Health 

Edwin Clark, II, Department of Natural Resources Rolf Hartung, University of Michigan, Ann Arbor 

and Environmental Control, State of Delaware Matthew Longnecker. Harvard School of 

Larry Gordon, New Mexico Health & Environmental Dept. Public Health, Boston 

Betty Olson, University of California, Irvine 



CIIWQP Subcommittee on Quality Assurance/Quality Control 



Ernest Angino, University of Kansas, Lawrence 
J. Phyllis Fox, J. Phyllis Fox Consulting Services 



Susan Jo Keith, City Managers Office, Phoenix 
Robert Meglen, University of Colorado, Denver 



CIIWQP Subcommittee on Treatment Technologies 

Georges Belfort, Rensselaer Polytechnic Institute, Troy Isadore Nusbaum, Consulting Engineer 

Vernon Snoeyink, University of Illinois, Urbana 



FEDERAL/STATE INTERAGENCY STUDY TEAM 

Edgar Imhoff, Program Manager Stephen Moore, US Fish and Wildlife Service 

Carroll Hamon, Deputy Program Manager and Representative 

CA Department of Water Resources Representative Larry Puckett, CA Department of Fish and Game 

Henry Hansen, US Bureau of Reclamation Representative Representative 

Walter Swain, US Geological Survey Representative 



Karen Beardsley 
Norman Coontz 
Steven Detwiler 
Ariel Dinar 
Patrick Gaul 



David Hansen 
Leila Horibata 
Robert Horton 
Steven Kasower 
Paul Lesneski 



Virginia Linares 
Maria Macoubrie 
Marjory McKenzie 
George Nishimura 
Tammy Pellish 



Abraham Philip 
Nigel Quinn 
Susan Sarantopoulos 
Craig Stroh 
David Sullivan 



Donald Swain 
Mark Weegar 
Kelly Williams 
Joy Winckel 
Marvin Yates 



XIU 



Chapter 1. SUMMARY OF THE PLAN AND 
RECOMMENDATIONS FOR ACTION 



This report summarizes the results of an intensive study of the subsurface agricultural drainage 
problems of the western side of the San Joaquin Valley, and presents a plan and 
recommendations for managing those problems from 1990 to 2040. The study has led to a much 
better understanding of the causes and effects of the drainage and drainage-related problems, 
although much is yet to be learned and long-term monitoring of the problem will be necessary. 

The study and resulting plan focus on in-valley management of the drainage and drainage-related 
problems. It appears that in-valley actions can manage the problems for several decades without 
a means of exporting drainage-related salts to the ocean. Ultimately, it may become necessary to 
remove salt from the valley. 

The recommended plan, which is regional in both scope and detail, takes account of uncertainties 
in information. The plan is not site-specific, and. without more detailed analysis, it is not a plan 
from which structures may be built. Rather, it should be considered as a framework that will 
permit the present level of agricultural development in the valley to continue, while protecting fish 
and wildlife and helping to restore their habitat to levels existing before direct impact by 
contaminated drainage water. It is noteworthy that many of the valley's water and drainage 
districts and individual growers have already begun to take actions similar to those recommended 
in this report. 

Figure 1 shows the San Joaquin Valley, the principal study area, and the five subareas used for 
planning. 

SUMMARY OF THE PLAN 

The plan recommended for management of subsurface drainage and drainage-related problems 
on the western side of the San Joaquin Valley contains the following major components: 

• Source control. Consisting mainly of on-farm improvements in the application of irrigation 
water to reduce the source of deep percolation. This in turn will reduce the amount of 
potential drainage problem water. 

• Drainage reuse. A planned system of drainage-water reuse on progressively more 
salt-tolerant plants. This will reduce the volume of drainage water and concentrate salts 
and trace elements for easier containment and safe disposal. 

Evaporation system. Drainage-water evaporation ponds planned for storage and 
evaporation of drainage water remaining after reuse on salt-tolerant plants. Four types of 
ponds are included: (a) Nontoxic ponds in which selenium in drainage-water 



Figure 1 

PROGRAM STUDY AREA 



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inflow is less than 2 parts per billion (ppb); (b) selenium-contaminated ponds (inflowwater 
containing selenium in the range of 2 to 50 ppb) that must include safeguards for wildlife 
and an equivalent area of alternative freshwater habitat; (c) small selenium-contaminated 
ponds designed with facilities to greatly accelerate the rate of evaporation, thereby 
reducing the pond surface area; and (d) temperature-gradient solar ponds that generate 
electricity by using water from other ponds containing very high salt and trace-element 
concentrations. 

• Land retirement. Cessation of irrigation of areas in which underlying shallow ground water 
contains elevated levels of selenium and the soils are difficult to drain. 

• Ground-water management. Planned pumping from deep within the semiconfined aquifer, 
in places where near-surface water tables can be lowered and the water pumped is of 
suitable quality for irrigation or wildlife habitat. 

• Discharge to the San Joaquin River. Controlled and limited discharge of drainage water 
from the San Joaquin Basin portion of the study area to the San Joaquin River, while 
meeting water-quality objectives. 

• Protection, restoration, and provision of substitute water supplies for fish and wildlife habitat. 

Provision of freshwater supplies to substitute for drainage-contaminated water previously 
used on wetlands and to allow protection and restoration of contaminated fisheries and 
wetland habitat. 

Institutional change. Includes tiered water pricing, improved scheduling of water deliveries, 
water transfers and marketing, and formation of regional drainage management 
organizations to aid in implementing other plan components. 

Table 1 summarizes the extent to which each plan component is included in the plan, based on the 
land area to which it applies or occupies and the water assigned for fish and wildlife uses. 



Table 1. SUMMARY OF RECOMMENDED DRAINAGE MANAGEMENT PLAN 





Subarea 


Plan Component 


Northern' 


Grasslands 


Westlands 


Tulare 


Kern 


Total 






Land areas in 1,000s of acres by 2040 




Source Control 





93.6 


159.3 


316.7 


105.9 


675.5 


Drainage Reuse" 





2.6 


12.1 


24.5 


9.7 


48.9 


Evaporation System" 





0.2 


2.1 


3.0 


2.3 


7.6 


Evaporation Pond" 





0.12 


0.40 


2.9 


1.07 


4.5 


Alternative Habitat 














Land Retirement 





3.0 


33.0 


7.0 


32.0 


75.0 


Ground Water Management 





10.0 


19.0 


40.0 


0.0 


69.0 


Discharge to San Joaquin River (land area) 





160.6 











160.6 




1,000s of acre-feet annually by 2040 


Increased Water for Fish and 





150.0'' 


4.0' 


29.0= 


11.0' 


194.0 


Wildlife Uses, Including Substitute Water' 















Except for study and monitoring, no planned drainage management actions are recommended for the Northern Subarea. 
The acreages shown are for on-site facilities; the total land area served is essentially all the area under source control. 
Substitute water is that water supply for wetlands that replaces contaminated drainage water used through the mid-1980s. 
Consists of 129,000 acre-feet of substitute water supply for wetlands, 20,000 acre-feet of Merced River instream 
fish flow m October, and 1,000 acre-feet of evaporation pond alternative habitat. 
Water for evaporation pond alternative habitat at the rate of 10 acre-feet/acre^ear. 



No planned drainage management actions other than those being carried out currently are 
recommended for the Northern Subarea. However, drainage water from this area now flows to 
the San Joaquin River. In the event that water-quality objectives for the river become more 
restrictive, actions that would aid in meeting the objectives are discussed in the subarea plan. 

Problem water is a term introduced in this report to describe the volume of near-surface ground 
water that, if reduced by source control or removed from plant root zones each year, would 
eliminate the drainage-related impediment to agricultural productivity. When placed in streams 
or open basins, some problem water is potentially hazardous to fish and wildlife and therefore 
must be managed to prevent environmental degradation. Drainage water that causes 
unacceptable levels of environmental degradation is viewed also as problem water for agriculture 
because it must be remedied — even if retirement of irrigated land is required. Table 2 shows the 
estimated reduction of problem water to be achieved by each plan component in each subarea. If 
the targets are met, agricultural production could be maintained for at least the duration of the 
planning period, without removal of salt from the valley. If salt export becomes necessary in the 
future, the actions recommended in this plan could create prerequisite conditions by providing 
collection facilities, by reducing drainage water volumes, and by isolating and controlling 
contaminants. 

Table 2. PROBLEM WATER REDUCTION, 2040 













Subarea 










Plan Component 


Northern 


Grasslands 


Westlands 


Tulare 


Kern 






Acre- 


Percent 


Acre- 


Percent 


Acre- 


Percent 


Acre- 


Percent 






feet 


of Total 


feet 


of Total 


feet 


of Total 


feet 


of Total 


Source Control 





32.7 


(21) 


55.8 


(36) 


63.2 


(30) 


37.1 


(34) 


Drainage Reuse 





13.6 


(9) 


61.0 


(40) 


113.3 


(54) 


43.6 


(39) 


Evaporation System 





0.7 


— 


4.0 


(3) 


12.3 


(6) 


6.0 


(5) 


Land Retirement 





2.3 


(1) 


24.8 


(16) 


4.2 


(2) 


24.0 


(22) 


Ground-water Manage- 





4.0 


(3) 


7.6 


(5) 


16.0 


(8) 





(0) 


ment 




















Discharge to San 





102.1 


(66) 





(0) 





(0) 





(0) 


Joaquin River 




















TOTAL 




155.4 


(100) 


153.2 


(100) 


209.0 


(100) 


110.7 


(100) 



a Except for study and monitoring, no planned drainage management actions are recommended for the Northern Subarea. 



The costs of the recommended plan have been annualized over the 50-year planning period, 
1990-2()4(). at an interest rate of 10 percent (Table 3). One-time costs include those for installation 
of facilities and purchase (as in the case of land retirement) of plan components. The category 
"Agricultural Drainage" includes all drainage-related components of the recommended plan, 
except on-farm drainage systems. "On-Farm Drains" includes new on-farm drainage systems 
expected to be installed between 1991 and 2040 and the annual operation of those drains during 
that period, as well as those already operating in 1990. "Fish and Wildlife" includes the costs of 
constructing and operating facilities and purchasing water so that clean water could be delivered 
to wetland habitat formerly supplied with contaminated drainage water. 

The economic value of the direct benefits or regional economic impacts of implementing the 
recommended plan was not estimated, and no allocation of costs among beneficiaries has been 



performed. For drainage reuse, an estimate of the value of wood produced has been reflected as 
a cost offset. However, for source control and land retirement, any economic surplus that might 
result from the possible transfer of conserved water to other uses has not been included as a cost 
offset. 

Table 3. ANNUALIZED COSTS OF THE RECOMMENDED PLAN 

In $1, 000s 

Agricultural Drainage 

One-time 

Source control 2,940 

Drainage reuse 6,194 

Evaporation system 3,043 

Land retirement 2,818 

Ground-water management 962 

San Luis Drain 2,300 

Subtotal 18,257 

Operation, maintenance, and replacement 

Source control 5,444 

Drainage reuse 2,291 

Evaporation system 1,915 

Land retirement 300 

Ground-water management 2,694 

San Luis Drain 390 

Subtotal 13,034 

TOTAL 31,291 

On-Farm Drains 

Installation 6,473 

Operation, maintenance, and replacement 1.536 

TOTAL 8,009 

Fish and Wildlife 

Installation 153 

Operation, maintenance, and replacement 18 

Water supply 2,548 

TOTAL 2,719 

GRAND TOTAL 42,019 



CONCLUSIONS AND RECOMMENDATIONS FOR ACTION 

During this study, a massive amount of data has been collected; many reports have been 
published; and much analysis, planning, and public review have been completed. This has led to 
the plan for drainage management presented in Chapter 6. However, a plan alone will not 
manage or solve the drainage and drainage-related problems of the western side of the San 
Joaquin Valley; actions are required on many fronts to make the plan a reality. These actions can 
be grouped under implementation, planning, monitoring, additional study, and funding proposed 
actions. The conclusions and recommendations for action that follow are presented in each of 
those groups. 

Implementation 

Local initiatives need to be recognized, supported, and enhanced by coordinated, comprehensive 
Federal and State actions undertaken to manage drainage problems. Several components in the 
management plan are either being studied preparatory to action or are actually being carried out 
by organizations and private interests in the problem area. Those activities that meet the criteria 
and objectives of the long-term drainage management plan should be carried out as rapidly as 
possible. Generally, these activities will require approval or assistance from local. State, or 
Federal agencies. They should receive high priority. 

Some changes in law and policy by local. State, and Federal agencies would provide the impetus 
or remove roadblocks for implementing some plan components. Policy actions by agencies 
supplying, distributing, and regulating irrigation water and managing drainage facilities are 
needed now and in the future. Institutional changes are also a part of the management plan, 
which requires concerted action by both the California Legislature and the U.S. Congress. 

Because unattended plans often do not materialize, the efforts reported here will be followed by a 
short, new Federal-State effort between October 1990 and December 1991 that will develop a 
strategy for implementation of the plan. 

Recommendation I - Implementation of Recommended Plan; Priority Activities 

Local, State, and Federal water organizations and authorities should consider the recommended 
plan and explicitly adopt those parts appropriate for their long-term strategy of contributing to 
the management or solution of the drainage problems of the west side San Joaquin Valley. 

The following plan components should be implemented as soon as final planning is complete, 
funding and applicable clearances can be obtained, and agreement can be reached. An asterisk 
(*) following a plan component indicates there is a related current local initiative that should 
become part of the plan component. 

Northern Subarea 

• Investigate, in detail, measures that may be needed if stricter salt standards are 
established for the San Joaquin River/Delta. 



Grasslands Subarea 

• Use the Grassland Task Force water districts as the nucleus of a regional drainage entity 
to coordinate and jointly manage subarea-wide drainage problems. * 

• Provide the facilities required to intercept contaminated subsurface drainage water now 
being discharged into open channels within the grasslands wildlife habitat, and convey 
these to the San Luis Drain. 

• Renovate and extend the San Luis Drain, bypassing 20,000 acre-feet of contaminated 
drainage water around wetlands (similar to the Zahm-Sansoni-Nelson plan). * 

• Improve on-farm water conservation and source control on all irrigated lands and reduce 
deep percolation on lands having drainage problems by 0.35 acre-feet per acre per year 
(on the average) as soon as possible. * 

Intensify and complete local demonstration projects on source control and treatment of 
drainage water. (Work already under way in Broadview, Panoche, and Pacheco water 
districts.) * 

• The U.S. Bureau of Reclamation should actively seek authority to reallocate 

74,000 acre-feet of water annually from the Central Valley Project to replace drainage 
water used on wetlands before 1985. 

• Restore drainage-contaminated wetlands. 

• Provide 20,000 acre-feet of water to the Merced River each October to attract migrating 
fish from drainage water discharging to the San Joaquin River. 

Westlands Subarea 

• Improve on-farm water conservation and source control on all irrigated lands and reduce 
deep percolation on lands having drainage problems by 0.35 acre-feet per acre per year 
(on the average) as soon as possible. * 

• Accelerate the pace and increase the number of field demonstrations of source control 
measures and drainage water treatment research, including especially reuse of drainage 
water on trees and removal of selenium from drainage water. * 

Develop guidelines for retirement of irrigated lands that have high selenium 
concentrations in shallow ground water and that are difficult to drain. 

• Design and develop a 5,000-acre demonstration unit of closely-spaced, low-volume wells in 
the semiconfined aquifer for planned drawdown of the high water table. 

Tulare Subarea 

• Develop a formal association of water districts (built around the existing Tulare Lake 
Drainage District) for coordinated and joint management of subarea-wide drainage 
problems. * 

• Improve on-farm water conservation and source control on all irrigated lands and reduce 
deep percolation on lands having drainage problems by 0.2 acre-feet per acre per year (on 
the average) as soon as possible. * 



• Accelerate the pace and increase the number of field demonstrations of source control 
measures and evaporation pond experiments, including especially the reuse of water on 
trees and modification of pond systems and their management to make ponds bird-free or 
bird-safe. * 

• Demonstrate in the field the use of alternative safe-water habitat near an existing 
evaporation pond containing elevated levels of selenium. 

• Design and develop a 5,000-acre demonstration unit of closely-spaced, low-volume wells in 
the semiconfined aquifer for planned drawdown of the high water table in the area of 
good quality ground water in the Kings River Delta (Tulare Subarea water quality zone E). 

Kern Subarea 

• Kern County Water Agency and local water districts should form a drainage management 
entity responsible for coordination and joint management of subarea-wide drainage 
problems. 

• Improve on-farm water conservation and source control on all irrigated lands and reduce 
deep percolation on lands having drainage problems by 0.35 acre-feet per acre per year 
(on the average) as soon as possible. * 

• Initiate intensive studies of the ground-water resources of the old Buena Vista and Kern 
lakebeds. 

Recommendation 2 - Source Control 

The agencies with major responsibility for delivery of water to the study area (U.S. Bureau of 
Reclamation and California Department of Water Resources) should increase their work with the 
university extension systems and water districts to demonstrate ways to improve the efficiency of 
irrigation water application and thereby reduce potential drainage-water volumes. 

Each water district should, by 1992, set objectives in their operation plans that would reduce deep 
percolation by the amounts stated in Recommendation 1 (preceding). State and Federal agencies 
should help local water districts accomplish their water conservation improvement plans. 

Recommendation 3 - Financing Source Control Measures 

Both the Federal and State governments should explore ways of providing a portion of the 
financing needed to implement irrigator source-control actions and to invigorate existing 
programs. The U.S. Soil Conservation Service and U.S. Bureau of Reclamation both have 
programs that could aid in financing irrigator actions. The State of California, through the 
Department of Water Resources, the Department of Food and Agriculture, and the State Water 
Resources Control Board, could provide loans and grants for source-control actions, if funds were 
made available. 



Recommendation 4 - Joint Technical Assistance 

The U.S. Department of the Interior and the State of California should jointly develop a technical 
assistance program to ameliorate the drainage problem, by providing water districts with 
geohydrologic and economic information and analytical techniques useful in investigating local 
areas for possible conjunctive surface- and ground-water use, land retirement, on-farm drainage, 
source control, and reuse. Technical assistance is also needed in environmental impact 
assessment, toxicity assessment, and habitat restoration. 

Recommendation 5 - State of California Lead in Water Conservation 

The State of California should expand and intensify its program of on-farm water conservation to 
focus especially on demonstrating alternative source control measures on drainage-problem lands. 

Recommendation 6 - Federal and State Programs' Adjustment 

The State of California and the U.S. Department of the Interior should jointly consider the 
findings, forecasts, and plans of the Drainage Program with respect to drainage problems, and 
should look for opportunities to encourage amelioration and resolution of these problems. This 
should be achieved through ongoing operations, planning, construction, 
and — if considered necessary — new legislation, promulgation of rules and regulations, and 
appropriate language in contracts and administrative reviews. 

Recommendation 7 - Western U.S. Applications 

The U.S. Department of the Interior should consider the information, techniques, and experience 
accumulated in the Drainage Program and extend appropriate aspects of the knowledge base to 
other land areas in the western United States that are experiencing similar agricultural drainage 
and drainage-related problems. 

Planning 

The general plan for reducing or solving drainage and drainage-related problems outlined in this 
report provides a framework into which many actions can be fitted. However, before many of the 
actions can move forward, additional work is needed to refine estimates of their scope and effects. 
Generally, this additional planning will occur at local, State, and Federal levels, and at 
combinations of each. 

Recommendation 1 - Water District Plans 

With financial and technical assistance from State and Federal agencies, water districts should 
lead in developing plans to: 

• Identify lands in drainage problem areas in which the combined characteristics of high 
concentrations of selenium and difficult-to-drain soils would make these lands candidates 
for retirement from irrigation. 

• Identify locations in drainage problem areas where there may be an opportunity to lower 
the high water table by pumping from deep in the semiconfined aquifer (above the 
Corcoran Clay), and design the facilities, reach agreements, and obtain policy approvals 
required to carry out pumping. 



Recommendation 2 - State Water Project Area 

Within the State Water Project service area, the State of California should lead in planning for the 
regional drainage-water treatment and disposal needs that will arise from management and reuse 
of drainage water within local water districts. 

Recommendation 3 - Federal Water Service Area 

Within the Federal water service area, the Department of the Interior should lead in planning for 
the regional drainage-water treatment and disposal needs that will arise from management and 
reuse of drainage water within local water districts. 

Recommendation 4 - Joint Planning for Ground-Water Management 

Plans for installation and operation of well fields designed to pump from the semiconfined aquifer 
to lower the high water table should be completed cooperatively by Federal and State agencies 
and water districts. In the Federal service area, the Bureau of Reclamation should work with 
Westlands, Broadview, Panoche, San Luis, and Firebaugh Canal water districts to design well 
fields for areas identified in this report. In the State service area, the Department of Water 
Resources should work with Kern County Water Agency and Empire Westside, Riverside. 
Stratford, and Laguna irrigation districts. Lakeside Irrigation Water District, Kings County Water 
District, and Kings River Conservation District for the same purpose. Services of the U.S. 
Geological Survey should be used in locating favorable areas and in developing plans. 

Recommendation 5 -Joint Planning for Water Delivery 

Federal and State fish and wildlife agencies, in cooperation with private wetland owners, and 
Federal and State water development agencies should jointly plan the facilities required for 
delivery of water to wildlife areas affected by subsurface drainage water. 

Monitoring 

To properly implement management of drainage and drainage-related problems, both the 
problems and the progress in solving them must be monitored. This is especially important 
because of the changing nature of the drainage problem and the flexible array of measures 
required for management. Monitoring all aspects of the problem and the effects of management 
will be critical to using the plan as a flexible guide to remedial actions. 

Recommendation I - Local Water Agencies 

All local water supply and drainage agencies should participate in joint, coordinated programs to 
monitor the volume and quality of drainage water in the collection, treatment, and/or disposal 
systems. 



10 



Recommendation 2 - Joint State/ Federal 

The U.S. Department of the Interior and the State of California should jointly design a 
scientifically reliable and cost-effective network of physical and biological monitoring stations that 
will detect change in the environment caused by subsurface agricultural drainage problems and 
attempts to solve these problems. Areas expected to experience expansion of high water tables 
should be included. 

Additional Study 

During the six-year life of the Drainage Program, the absence of reliable information made it 
necessary for the Program to fund basic research, as well as to fund investigations directly 
relevant to solving drainage problems. Some additional study is needed to provide detailed 
information for feasibility determinations. 

Recommendation 1 - Study Needs 

Water and land managers, universities, agencies, and individuals should emphasize the following 
study categories and subjects, and support the development of information transfer programs to 
extend study results to appropriate user groups. 

Drainage Management 

Develop measures to renovate or close aged or toxic evaporation ponds. 

Develop a cost-effective treatment method to remove selenium from drainage water. 

Perform field tests of tolerance of agricultural crops, halophytes, and salt-tolerant trees to 
constituents in drainage water. 

Develop effective training programs for personnel involved in drainage management. 

Investigate the propagation and marketing of salt-tolerant crops that use saline drainage 
water as an irrigation supply. 

Demonstrate the use of an accelerated evaporation system, using a sprinkler system 
similar to the University of Texas at El Paso's experimental system and the use of a 
temperature-gradient solar pond system for salt disposal and generation of electricity. 

Geohydrology 

The following studies are interrelated by the nature of the geohydrologic system. The objective is 
to better understand the surface- and ground-water system's chemical and physical characteristics 
that will allow better management of the natural resources. 

Evaluate, in detail, the areal and vertical variability of ground-water quality in the Tulare 
Subarea and in all water-quality zones considered for the ground-water management 
component in the plan. 

Investigate solubility controls for specific elements of concern (selenium, arsenic, 
molybdenum, and uranium) in various geologic conditions. Specifically, expand studies to 
include basin and lacustrine environments that dominate the Tulare Basin where drain 
water disposal options are severely limited and conditions are highly varied. 



11 



• Develop reliable, consistent methods for estimating ground water pumping. 

Complete investigation of surface water and ground water interaction in the San Joaquin 
River so that the quantity, quality and timing of ground-water contributions to river flows 
can be evaluated. 

• Complete development of a streamflow and solute transport model for the San Joaquin 
River and couple it with reservoir operations models so that management alternatives can 
be evaluated. 

• Determine the capacity of geochemically reduced Sierra Nevada sediments to remove 
selenium. 

Determine the hydraulic and water-quality feasibility of controlling the water table by 
pumping from wells in selected areas. 

Continue development of quantitative analyses of ground water flow systems. 

Economics 

• Use the surface and subsurface conjunctive-use model of the San Joaquin Valley (as 
developed for the Drainage Program) to evaluate water transfers and marketing scenarios. 

Fish and Wildlife 

Contamination. Continue the effort initiated by the Program to determine the nature, geographic 
extent, and severity of contamination of fish, wildlife, and their habitats by subsurface drainage 
water. Special attention should be given to: evaporation ponds and neighboring public and 
private wildlife areas; agroforestry plantations; the San Joaquin River, Delta, and San Francisco 
Bay; and the six substances of concern discussed in this report (arsenic, boron, chromium, 
molybdenum, selenium, and total dissolved solids) and ten additional trace elements and metals: 
cadmium, copper, lithium, manganese, mercury, nickel, strontium, uranium, vanadium, and zinc. 

Toxicity. Continue the effort initiated by the Program to define, for fish and wildlife, safe and 
toxic concentrations (and associated biological effects) of subsurface drainage water substances 
of concern in water and food. Special attention should be given to: independent toxicity of trace 
elements other than arsenic, boron, and selenium (for example, cadmium, chromium, copper, 
lithium, manganese, mercury, molybdenum, nickel, strontium, total dissolved solids, uranium, 
vanadium, and zinc); interactive effects of trace elements in drainage water; effects of water 
chemistry (for example, pH and salinity) on independent and interactive toxicity; and site-specific 
toxicity (for example, in valley aquatic and wetland habitats, evaporation ponds, and agroforestry 
plantations). 

Protection, restoration, substitute water supply, and improvement. Continue the effort initiated 
by the Program to identify and evaluate measures to: protect remaining fish and wildlife 
resources of the San Joaquin Valley from drainage-related impacts; restore drainage water 
contaminated habitats; provide water supplies to substitute for drainage water previously used by 
fish and wildlife; and improve fish and wildlife resources. 

Out-of-valley drainage water disposal. In the event that out-of-valley disposal is pursued in the 
future, develop information to assess the potential effects on fish and wildlife habitats and 



12 



populations, and public uses of those resources in the receiving waters and lands. In light of 
recommendations for consideration of disposal in these areas, special attention should be given to 
the Sacramento-San Joaquin Delta, San Francisco Bay, and the Pacific Ocean (CVRWQCB, 
1988a; NRC, 1989). 

Public Health 

To adequately quantify the risks of environmental chemical exposures, substantial information is 
necessary on the environmental fate of the chemicals, the toxicity of specific forms, and the degree 
to which humans are exposed to them. Although site- and organism-specific data are always 
preferred, surrogate data are used frequently to fill data gaps (for example, animal studies are 
extrapolated to assess likely human toxicity resulting from a chemical exposure). The following 
summarizes information needed to best assess the probability of adverse human health effects 
related to drainage contaminant exposures. 

Environmental fate 

• Further identify chemical forms of substances of concern in different environmental media 
(air, water, soil, sediment, biota). 

• Further identify environmental conditions (pH, oxidation-reduction, etc.) in which 
different chemical forms of substances of concern occur in different environmental media. 

• Continue studies conducted by the University of California to assess the uptake of 
substances of concern into edible biota related to specific environmental conditions. 

• Place research emphasis on the environmental fate of substances of concern via typical 
routes of human exposure (for example, food-chain transfer of organic forms of trace 
elements). 

Toxicology 

• Perform additional chronic toxicity testing on specific chemical forms of substances clearly 
associated with the drainage problem. 

Exposure assessment 

• Further identify contaminant threshold concentrations in edible animals in tissues used for 
human consumption. 

Further identify contaminant threshold concentrations in edible plants in tissues used for 
human consumption. 

• Characterize consumption patterns of populations at risk. 
Risk quantification 

• Quantify option- and site-specific public health risks. 

Funding Proposed Actions 

There has been no formal discussion or analysis of the way in which components of the plan and 
the various actions recommended would be funded. Undoubtedly the costs would be shared by 



13 



the private and public sectors and it is essential that discussion begin soon of distribution of plan 
costs. 

Recommendation 1 - Cost Allocation Principles 

The following principles should be considered in discussing allocation of the costs of 
implementing the plan. 

All areas contributing to a problem of subsurface agricultural drainage water should share 
in the costs of resolution and management of that problem. 

• With respect to contributing areas, the cost-sharing formulas should be based on best 
available scientific information, and they should be re-evaluated and updated periodically 
in light of new information. 

• Both direct indicators (upslope-downslope hydraulic relationships, for example) and 
indirect indicators (water supply received, for example) should be considered for inclusion 
in cost-sharing formulas. 

• All beneficiaries should pay for drainage-management costs in proportion to benefits 
received. 

• There are both market and nonmarket national. State, and local benefits to be realized 
from the management of drainage problems. All beneficiaries should be identified. 

• Because of the widespread occurrence of the drainage problem on the western side of the 
valley and the lack of scientific data on specific sites, costs should be distributed over the 
largest practicable land area — a whole service area or an association of water districts, 
for example — rather than one small water district. 

Recommendation 2 - Study Plan Benefits 

The U.S. Department of the Interior and the State of California should jointly study the benefits 
of implementation of the plan. 

Recommendation 3 - Study Legislative Needs 

The State of California should examine the need for new legislation to remove obstacles or to 
create opportunities for water marketing so that funds from water sales may be used for payment 
of drainage costs. 



14 



Chapter 2. THE PROBLEM 



The San Joaquin Valley, which forms the southern portion of California's Central Valley, is 
bounded on the east by the Sierra Nevada and on the west by the Coast Ranges (Figure 1). 
It is made up of two geologic features — the San Joaquin Basin, drained by the San Joaquin 
River, and the Tulare Basin, a hydrologically closed basin that is is drained by the river only 
in extremely wet years. The two basins divide the San Joaquin Valley roughly into its north- 
ern and southern halves. 

The general study area includes the entire San Joaquin Valley, from the drainage divide of the 
coastal mountains to the 1,000-foot elevation of the Sierra Nevada foothills. The principal 
study area comprises lands that are now directly affected by or contribute to agricultural sub- 
surface drainage problems, as well as lands likely to be directly affected in the future. Most 
of these lands are on the western side of the valley and at its southern end. 

A BRIEF HISTORY 

The conditions associated with agricultural drainage in the San Joaquin Valley are not new to 
the region. Inadequate drainage and accumulating salts have been persistent problems in 
parts of the valley for more than a century, making some cultivated land unusable as far 





.Wr" . ^^WIH^HHI^HH^^Hfe^^ ' ^^^^r'l^H 


IHHI 


. ^ - . ^s^^m^ 


i^R^HI^SBI 






.-0-:- 


'^^?^S^^^2 


■^"'^■?^"^ 


-' ^^^^^R 


-•^■i- ., 


'"'^*>j[^^|£^^f^^S»ij 


- . ' 


'^^^^gjt^-'., 











Agricultural land 
south of Los Banos 
damaged by salt 
deposits caused by 
evaporation from 
ground water lying 
only a few feet below 
the land surface. 



15 



back as the 1880s and 1890s (Ogden, 1988). Widespread acreages of grain, first planted on the 
western side of the valley in the 1870s and 1880s. were irrigated with water from the San Joa- 
quin and Kings rivers. This type of farming spread until, by the 1890s. the rivers' natural flows 
were no longer adequate to meet the growing agricultural demand for water. Poor natural 
drainage conditions, coupled with rising ground-water levels and increasing soil salinity, meant 
that land had to be removed from production and some farms ultimately abandoned. 

The development of irrigated agriculture in the San Joaquin Valley since 1900 owes a great 
deal to the improvements in pump technology that took place in the 1930s. These achieve- 
ments led to the development of large turbine pumps that could lift water hundreds of feet 
from below ground. In time, heavy pumping triggered severe ground water overdraft because 
more water was being extracted than was being replaced naturally. Ground water levels and 
hydraulic pressure fell rapidly, and widespread land subsidence began to occur. By the late 
1950s, estimated overdraft in Kern County had reached 750,000 acre-feet per year. 

Initial facilities of the Federal Central Valley Project transported water from Northern Cali- 
fornia through the Sacramento-San Joaquin Delta and the Delta-Mendota Canal in 1951 to 
irrigate 600,000 acres of land in the northern part of the San Joaquin Valley. This water pri- 
marily replaced and supplemented San Joaquin River water that was diverted at Friant Dam 
to the southern San Joaquin Valley. 

The CVP's San Luis Unit and the State Water Project, each authorized in 1960, began deliv- 
ering Northern California water to agricultural lands in the southern San Joaquin Valley in 
1968. Together they provide water to irrigate about 1 million acres. Authorization of the San 
Luis Unit also mandated construction of an interceptor drain to collect irrigation drainage 
water from its service area and carry it to the Delta for disposal. The Bureau of Reclama- 
tion's 1955 feasibility report for the San Luis Unit described the drain as an earthen ditch 
that would drain 96,000 acres. By 1962, Reclamation's plans had changed to a concrete-lined 
canal to drain 300,000 acres. In 1964, alternative plans added a regulating reservoir to tempo- 
rarily retain drainage (USBR, 1964). A decision was made in the mid-1970s to use the reser- 
voir to store and evaporate drainage water until the drainage canal to the Delta could be 
completed. 

At this same time, questions were raised about the potential effects of untreated agricultural 
drainage on the quality of water in the Delta and San Francisco Bay. This concern was re- 
flected in a rider added to the CVP appropriations act by Congress in 1965, which stated that 
". . . the final point of discharge for the interceptor drain for the San Luis Unit shall not be 
determined until development by the Secretary of the Interior and the State of California of a 
plan which shall conform with the water quality standards of the State of California as ap- 
proved by the Administrator of the Environmental Protection Agency." This proviso remains 
in effect today. 

Initially, the San Luis Drain was conceived as a State/Federal facility, but the State twice de- 
clined to participate. The Bureau of Reclamation began construction in 1968 and, by 1975, 
had completed 85 miles of the main drain, 120 miles of collector drains, and the first phase of 
the regulating reservoir (Kesterson). In 1970, Kesterson Reservoir became part of a new na- 
tional wildlife refuge managed jointly by Reclamation and the U.S. Fish and Wildlife Service. 



16 




Diked ponds in Kesterson Reservoir fed by the San Luis Drain (open canai in mid-pho- 
to) In the eariy 1980s. 



Federal budget constraints and growing environmental concern about releasing irrigation run- 
off into the Delta halted work on the reservoir and the drain. 

In 1975, the Bureau of Reclamation, the California Department of Water Resources, and the 
State Water Resources Control Board formed the San Joaquin Valley Interagency Drainage 
Program to find a solution to valley drainage problems that would be economically, environ- 
mentally, and politically acceptable. This group's recommendation was to complete the drain 
to a discharge point in the Delta near Chipps Island (IDP, 1979). In 1981, Reclamation be- 
gan a special study to fulfill requirements for a discharge permit from the State Water Re- 
sources Control Board. 

The 1983 discovery of deformities and deaths of aquatic birds at Kesterson Reservoir altered 
the perception of drainage problems on the western side of the valley. Selenium poisoning 
was determined to be the probable culprit. In 1984 the San Joaquin Valley Drainage Pro- 
gram was established as a joint Federal and State effort to investigate drainage and drainage- 
related problems and to identify possible solutions. 

In 1985, the Secretary of the Interior ordered that discharge of subsurface drainage to Kester- 
son be halted, and the feeder drains leading to the San Luis Drain and the reservoir were 
plugged in 1986. The reservoir is now closed. The vegetation has been plowed under, and 
low-lying areas were filled in 1988. 



17 



Contamination-related problems similar to those identified at Kesterson are now appearing 
in parts of the Tulare Basin, which receives irrigation water from the State Water Project, in 
addition to other surface and ground water supplies. Wildlife deformities and deaths have 
been observed at several agricultural drainage evaporation ponds. 

THE AREA OF CONCERN 

The chief area of concern in this study is the western side of the San Joaquin Valley from the 
Sacramento-San Joaquin Delta on the north to the Tehachapi Mountains south of Bakers- 
field. This area coincides generally with the Federal Delta-Mendota Canal and San Luis Unit 
irrigation service areas and the State Water Project service area. Figure 2 shows those service 
areas, the Friant-Kern Service area on the eastern side of the valley, and the general study 
area boundary. Lands now directly affected by, contributing to, or likely to be directly af- 
fected by agricultural drainage problems make up the principal study area shown on Fig- 
ure 1. To aid planning and analysis, the principal study area has been divided into the 
Northern, Grasslands, Westlands, Tulare, and Kern subareas. Subarea boundaries are based 
on hydrologic considerations, political boundaries, current drainage practices, and/or the 
nature of the drainage-related problems. 

The San Joaquin Valley is a gently sloping, nearly unbroken alluvial plain, about 250 miles 
long and an average of 45 miles wide, that is characterized by a mild, dry climate. The tem- 
perate climate, productive soils, and the application of water by farmers have combined to 
make this one of the world's most productive agricultural areas. Nearly all crops grown com- 
mercially in the region require irrigation. 

Soils on the western side of the valley are derived from the marine sediments that make up 
the Coast Range and are high in salts and trace elements that occur in a marine environment. 
Irrigation of these soils has dissolved these substances and accelerated their movement into 
the shallow ground water (Gilliom, et al., 1989a). Where water tables are high and agricultur- 
al drains are necessary, drainage water frequently contains elevated concentrations of these 
constituents. 

The principal study area includes remnant natural and managed habitats of importance to a 
diversity of fish and wildlife species. Habitats include the Grasslands area, a large 
grasslands/wetlands complex in the southern San Joaquin Basin, where for several decades 
commingled surface and subsurface agricultural drainage water was used for habitat manage- 
ment; the San Joaquin River, into which an estimated 35,000 to 56,000 acre-feet per year of 
collected subsurface agricultural drainage water is currently discharged; evaporation ponds 
(primarily in the Tulare Basin), where subsurface drainage water is discharged and concen- 
trated and which are used extensively by aquatic birds; and the beginnings of agroforestry 
plantations that are watered with subsurface drainage water and used by several terrestrial 
wildlife species. 

The principal study area is predominantly rural. Communities tend to have fewer than 
10,000 residents whose main economic existence is tied directly to agriculture. Although the 
population is sparse, compared to the central and eastern portions of the San Joaquin Valley, 
demographic shifts are occurring with an influx of people into the Tracy-Los Banos area from 
the San Francisco Bay region and into the Bakersfield area from the Los Angeles basin. Mi- 
grant farm workers also are major contributors to the area's economy and population. 



18 



Figure 2 

MAJOR FEDERAL AND STATE 
IRRIGATION FACILITIES AND SERVICE AREAS 



^ Sacramento '^ 




lEGENP 

I AUi i»ii' Edge of Valley Floor 

. — ^~ General Study Area Boundary 

Friant-Kern Service Area 

1^^^ CVP San Luis Unit Service Area 

l^^l CVP Delta-Mendota Canal Service Area 

H^H SWP Service Area 



19 



INTERESTS AFFECTED BY DRAINAGE PROBLEMS 

Agriculture 

Agriculture provides the economic base of the western side of the San Joaquin Valley (Archi- 
bald, 1990). About 90 percent of the 2,544,000 irrigable acres in the principal study area are 
in irrigated crop production at any one time. A diverse range of crops is grown there. Fruits 
and nuts are important in the Northern, Grasslands, and Kern Subareas, while the predomi- 
nant crops in the Tulare and Westlands Subareas are field crops and cereal grains. Cotton is 
the leading field crop in both subareas. 

Irrigation practices, methods, and efficiencies vary subarea by subarea. In 1980, the predominant 
method in the San Joaquin Valley was surface irrigation. The methods chosen depend on many 
factors — types of crops cultivated, cost of water, soil types, and current irrigation and drainage 
management practices. Farming practices and irrigation efficiencies are influenced by variations 
in soil type, climate, slope of the terrain, crops grown, and a grower's experience. 

If current irrigation practices continue, areas in which ground-water levels are 5 feet or less 
from the surface of irrigated lands will continue to expand in the Westlands, Tulare, and Kern 
subareas. Such areas in the Northern and Grasslands subareas are unlikely to increase as 
long as they can be drained to the San Joaquin River. The total area in the western side at 
that level now is about 847,000 acres, of which 90,000 acres are managed as wetlands. By 




MELONS 

Melons are an important crop In both the Grasslands and Westlands subareas. 



20 



2000, high ground-water levels may be adversely affecting about 1 million acres of irrigated 
land (W.C. Swain, 1990a and 1990b), or about 40 percent of irrigable farmland in the princi- 
pal study area. This will reduce crop productivity, cause loss of farm income through conver- 
sion from salt-sensitive to salt-tolerant crops, increase costs of drainage management, and 
force land out of production. 

Fish and Wildlife 

[The following section is supported by information in the Drainage Program 's 
Technical Report, Fish and Wildlife Resources and Agricultural Drainage in 
the San Joaquin Valley, California, October 1990./ 

Before settlement of the San Joaquin Valley began in the 19th century, the richly diverse land- 
scape supported large populations of both resident and migratory species of fish and wildlife. 
Today, most of these aquatic, wetland, riparian forest, and valley oak savannah habitats have 
been converted to agricultural, municipal, and other uses. Less than 1 percent of the fresh- 
water lakes, only about 7 percent of the riparian forests, and less than 15 percent of the origi- 
nal wetlands remain. As a result, some native plants and animals have vanished from the 
landscape, and the continued existence of many others is in serious jeopardy. The popula- 
tions of birds that once lived in or visited the valley as migrants have been greatly reduced, 
and the grizzly bear, the pronghorn antelope, and the gray wolf have disappeared entirely. 

Impoundments on and diversions from the San Joaquin River and its tributaries have dra- 
matically reduced the valley's fisheries. Native fish have declined drastically and introduced 
species are now dominant. Chinook salmon, once sufficiently abundant to have at least a 
spring run and a fall run, have been greatly reduced in population. 

About 200,000 acres of private and public land and water in the San Joaquin Valley are pres- 
ently managed as parks, refuges, and preserves, primarily for the benefit of fish and wildlife. 
These areas, which protect the surviving native habitats, include State and Federal wildlife 
areas. State fishery facilities, private duck clubs, special management areas, and private na- 
ture preserves. Until recently, about half the water supplies used in these areas was provided 
by agricultural drainage, but use of drainage water for such purposes has been discontinued 
on almost all wildlife areas because it may endanger the health of fish and wildlife. The loca- 
tion of major public wildlife areas in the San Joaquin Valley is shown in Figure 3. 

Laboratory research has demonstrated that elevated waterborne and/or dietary concentra- 
tions of several trace elements in some San Joaquin Valley drainage waters are toxic to fish 
and wildlife. Selenium is the most prominent of these; other constituents of concern include 
arsenic, boron, chromium, molybdenum, and salts. 

Water Quality 

The State of California, through the State Water Resources Control Board (State Board) and 
the nine Regional Water Quality Control Boards (Regional Boards), is responsible for pro- 
tecting the quality of the State's water for beneficial uses. Regulation of deleterious waste 
discharges into both surface and ground water of the State is their responsibility. The Cen- 
tral Valley Regional Water Quality Control Board has adopted and the State Board has ap- 
proved objectives for allowable concentrations of selenium, boron, and molybdenum at vari- 
ous sites on the San Joaquin River and tributaries (CVRWQCB, 1988a). [The U.S. Environ- 



21 



Figure 3 

MAJOR PUBLIC WILDLIFE AREAS IN THE SAN JOAQUIN VALLEY 



...»•■'* 



FMbm' 



O 



|. 



/■ 



\ Sacramento \,^ 



\V> 



kelun''*, 



Riven 



•Stockton 



^ 



'■■: /CN'~*CV^ 


Stanislaus..^ 






r 




Tuolumne 




% 


J^ 






2 


— t ^ i jl 




KL3 


jO A % W 




'Am ^ 


^ ^•^1 


li. 


^:^ 



t« 



^ 



%, 



'<^ 



River/ 



10 20 

I— J ' ' I 

MILES 




N 



LOCATION MAP 



Monterey Bay 



onterey 






X'^noche' 



'V. 



RIVER. 



tdota 

7 



*.„-$&- V 



ant* 



*V 



."%. 



Fresno 



River 






1 >\\\n-'iiii" Edge of Valley Floor \^^ 

^~* General Study Area Boundary \ 


^^*\ 
\ 


JtotlemartA Tulare Ukebed ^» ^\ 

► ^' o\ ■"' ''2' ''' J 


1 -San Joaquin River NWR 2-Kesterson NWf£)^ 






^i^^^r-A^ 


Bay \ 

3-San Luis NWR 4-VoltaWA / 


• San Luis Obispo 


\ s %- 


J^^^^^'Ba'kersfield^ 


5-Los Banos WA 6-Merced NWR 


^ 




"^^Buena Visia 

.^ --Kem Ukebed 


7-Mendota WA 8-Pixley NWR 


1 




*■"!"' •''ii'ir!]2te\ 



9- Kern NWR 

WA=Wildlife Area-State NWR=National Wildlife Refuge-Federal 



22 



mental Protection Agency, however, has disapproved certain of the Board's objectives, and 
the matter is presently unresolved.] State water-quality objectives now and in the future will 
limit the discharge of agricultural drainage water to be assimilated by these streams. The 
Regional Boards issue permits for construction and operation of drainage-water evaporation 
ponds. Since events at Kesterson, the Regional Boards have become more concerned about 
the operation and eventual closure of these facilities. 

Actions proposed by the Drainage Program are consistent with the State's present water- 
quality objectives. However, concern over the quality of the State's surface and ground water 
is expected to continue growing and introduction of agricultural drainage water into either 
body will likely be more strictly regulated in the future. In anticipation of these develop- 
ments and in view of new scientific findings, assumptions based on more stringent objectives 
have been included in the alternative plans in Chapter 5 to show changes in required actions 
and associated costs. 

Public Health 

For the most part, contaminated agricultural drainage water is most likely to harm humans 
through indirect contact, such as consumption of contaminated fish or wildlife, plants, or 
livestock (Klasing and Pilch, 1988). Hazards intensify when contaminants are bioconcen- 
trated by plants and animals or by evaporation, as in evaporation ponds. Direct dermal con- 
tact with drainage water contaminants studied to date is unlikely to pose significant health 
risks; however, inhalation of some particulate sediments (chromium, nickel, and silica, for 
example) has been shown to cause adverse health effects under some conditions. 

Public health effects have been considered during this study, and plans were based on a crite- 
rion to minimize potential adverse public health risks from any drainage-water management 
strategy. Conclusions from studies of various potentially harmful constituents of drainage 
water as public health risks are presented in Chapter 3. 



23 



Chapter 3. WHAT THE STUDY HAS 
REVEALED OR CONFIRMED 



When the San Joaquin Valley Drainage Program was initiated in late 1984, there were many 
questions and conflicting opinions about westside San Joaquin Valley drainage and 
drainage-related problems. Through Program-supported studies from 1985 to 1990, some 
questions have been answered, some myths discredited, and some controversy resolved; but 
other questions and issues remain. The drainage problem was a long time developing. It will 
likely be solved only through the diligence and cooperation of many individuals and 
organizations over a considerable period. Further study will undoubtedly be essential to 
these efforts. 

A common base of knowledge is paramount to understanding the causes and for developing 
potential solutions to drainage problems. This chapter describes major advancements in 
knowledge of various aspects of the drainage problem. 

GEOHYDROLOGY 

Understanding the geologic makeup and hydrologic characteristics of the study area is 
necessary to understanding the cause of the drainage problem. 

Geology 

The Corcoran Clay, a clay layer 20 to 200 feet thick that underlies all but a small part of the 
study area, was formed as a lakebed about 600,000 years ago and is an important geologic 
feature of the San Joaquin Valley (Figure 4). Lying as much as 850 feet deep along the Coast 
Ranges and 200 to 500 feet deep in the valley trough, the Corcoran Clay effectively divides the 
ground-water system into two major aquifers — a confined aquifer below it and a 
semiconfined aquifer above it (Page, 1986). 

In the San Joaquin Basin, the semiconfined aquifer can be divided into three geohydrologic 
units, based on the sources of the soils and sediments. These are Coast Range alluvium. 
Sierra Nevada sediments, and flood-basin deposits. The Coast Range alluvial deposits, which 
range in thickness from 850 feet along the slopes of the Coast Range to a few feet along the 
valley trough, were derived largely from the erosion of marine rocks that form the Coast 
Ranges and contain abundant salt. Some of the marine sediments contain elevated 
concentrations of selenium and other trace elements. The Sierra Nevada sediments on the 
eastern side of the valley generally do not contain elevated selenium concentrations. The 
flood-basin deposits are a relatively thin layer in areas of the valley trough that have been 
created in recent geologic time. These three geohydrologic units differ in texture, hydrologic 
properties, chemical characteristics, and oxidation state. 



25 



Figure 4 

GENERALIZED GEOHYDROLOGICAL CROSS-SECTIONS 
IN THE SAN JOAQUIN AND TULARE BASINS 

(Locations Shown In Figure 6) 



FEET 
600—1 



SEA LEVEL- 



SAN JOAQUIN BASIN (Panoche Fan) 




-600-1 



Horizontal Scale 
1 Mile 



(Confined Aquifer) 



CORCORAN CLAY 



MIXED ORIGIN SEDIMENTS 



Adapted from: Belitz.1988 and DWR,1987. 



FEET 
500-1 

SEA LEVEt 



B ' 
WEST 



TULARE BASIN 
Depth to Shallow Ground Water 



5-20 Feet 
-N 



0-5 Feet 



-1000- 



-2000 -I 



ALLUVIUM 



2 Miles 

1 I I 
Horizontal Scale 



■♦+*- 



5-20 Feet 



O 



O 



B' 
EAST 



w 2f 



Flood Basin ^^ 
Deposits (43) 




CORCORAN CLAY 



Adapted from: Page.1983 and DWR,1987. 
26 



In the Tulare Basin, the semiconfined aquifer consists of the same three geohydrologic units 
found in the San Joaquin Basin, plus one additional unit, Tulare Lake sediments. The Tulare 
Basin is characterized by the presence of several dry lakebeds, including Tulare, Buena Vista, 
and Kern. 

The marine sediments from which most soils in the study area are derived contain salts and 
potentially toxic trace elements, such as arsenic, boron, molybdenum, and selenium. When 
these soils are irrigated, the substances dissolve and leach into the shallow ground water 
(Gilliom, et al., 1989a). Selenium is largely a westside phenomenon. Soils derived from Coast 
Range sediments are generally far saltier than soils formed from Sierran sediments. In fact, 
selenium in livestock feed grown in some areas of the eastern side of the valley is so low that 
it must be added to the livestock diet. Figure 5 shows selenium in the top 12 inches of soil, 
as determined by a survey in the mid-1980s. Most soluble selenium has been leached from 
the soils over the past 30 to 40 years, and it now occurs in solution in the shallow ground 
water. It is drained from there when growers attempt to protect crop roots from salts and a 
high water table. Generally, growers need not be concerned about protecting crops from 
selenium. 

Surface Water 

Precipitation in the study area is low, ranging annually from 5 inches in the south to 10 
inches in the north. Virtually all rainfall occurs from November through April, and, by 
midsummer, the small natural flows in most westside streams have ended or dwindled to little 
more than trickles. Storage and development of irrigation facilities on eastside streams have 
reduced inflow to once-large lakes such as Tulare and Kern. Now water reaches their dry 
lakebeds only in extremely wet years, such as 1983. 




4 



Natural vegetation growing on the westside San Joaquin Valley without irrigation. 



27 



Figure 5 

SELENIUM CONCENTRATIONS IN SOILS 
(Total Selenium in Top 12 Inches of Soil) 




LEGEND 

i,..„,(i\i„...iiii„ gjjgg Qf Valley Floor 

^~ General Study Area Boundary 



Less than 0.09 ppm 
I I 0.10 to 0.13 ppm 

I 14 to 0.36 ppm 
I 1 0.37 to 1.07 ppm 



Adapted fromTidball et..al.,1986 



28 



The San Joaquin River and its major westside tributaries, Salt Slough and Mud Slough, are 
important to the study area because they convey drainage water away from the Northern and 
Grasslands subareas. San Joaquin River flows are controlled by dams on tributaries and on 
the main stem upstream from Fresno. Water stored in Millerton Reservoir is diverted 
through the Friant-Kern and Madera canals. Irrigation water historically diverted from the 
lower reaches of the San Joaquin River was replaced with Central Valley Project water 
provided through the Delta-Mendota Canal, beginning in 1951. Now, the San Joaquin River 
is essentially dry much of the year from below Gravelly Ford to the point at which irrigation 
return flow and local runoff replenish the river. Development on major eastside tributaries 
has also reduced the flow of the San Joaquin River. The combination of these actions causes 
problems in water quantity and quality, both for fish and for other downstream river users, 
especially in the South Delta area. 




Irrigation water is still pumped from both above and below the Corcoran Clay, especially 
during drought periods when surface water supplies are short. 



Ground Water 

Pumping of ground water for irrigation from 1920 to 1950 drew ground-water levels down as 
much as 200 feet in large portions of the study area (Belitz, 1988). High pumping costs, land 
subsidence, and declining water quality created a need for new water supplies. By 1951, 
Federal Central Valley Project water was being pumped from the Delta and delivered to the 
Northern and Grasslands subareas through the Delta-Mendota Canal. By 1968, water was 
being delivered to the Westlands, Tulare, and Kern subareas through facilities of the CVP's 
San Luis Unit and the State Water Project. 



29 



With a reliable supply of surface water, ground-water pumping for irrigation lessened and the 
ground-water reservoir gradually began to refill. The semiconfined aquifer above the 
Corcoran Clay is now fully saturated in much of the westside area. Water tables continue to 
rise, and the waterlogged area is expanding. During the period 1977-1987, the O-to-5-foot area 
expanded from 533,000 acres to 817,000 acres (WC. Swain, 1990a). Figure 6 shows areas in 
which the water table was less than 5 feet deep, 5 to 10 feet deep, and 10 to 20 feet deep 
during part of 1987. 

Irrigation-induced leaching of the soil and accumulation of salts from both the leaching and 
from imported water have concentrated dissolved salts in the upper portion of the 
semiconfined aquifer. Most of these salts are now located in a zone 20 to 150 feet below the 
ground surface (DuBrovsky and Neil, 1990). Ground-water quality is generally better above 
and below this zone. Figures 7 through 11 show concentrations of salinity, selenium, boron, 
molybdenum, and arsenic in shallow ground water (less than 20 feet below the land surface). 
This shallow ground water, and, in some places, water located even deeper, is the source of 
subsurface drainage water. 

There are still zones in the semiconfined aquifer above the Corcoran Clay in which ground 
water is present in quality and quantity suitable for irrigation. Figure 12 shows the location 
of zones with salinity less than 1,250 parts per million (ppm) for several aquifer thicknesses 
saturated with water of that quality. The map was prepared by using a geographic 
information system and combining and evaluating water quality data and well construction 
information for the study area, as obtained from the U.S. Geological Survey, the U.S. Bureau 
of Reclamation, the Department of Water Resources, the Central Valley Regional Water 
Quality Control Board, and local water agencies. The procedures used were designed to 
produce a conservative estimate of the total depth of ground water that meets the specific 
water quality criterion of 1,250 parts per million total dissolved solids. Lenses of good 
quality water (less than 1,250 ppm TDS) overlying poor quality water (more than 1,250 ppm 
TDS) were not included in the total depth calculations. In some areas, notably in the 
southern Westlands Subarea, data from studies conducted in the 1960s were used in the 
absence of more recent data. Elsewhere, data from 1970 to 1989 predominated (Quinn, 1990). 

DRAINAGE-WATER CONSTITUENTS 

Salinity 

Drainage water contains dissolved mineral substances often referred to as "salts." These 
salts include sulfates, chlorides, carbonates, and bicarbonates of the elements sodium, 
calcium, magnesium, and potassium. The term "salinity" refers to the salt content of 
solutions containing dissolved mineral salts, which is commonly measured as either total 
dissolved solids (TDS) in parts per million (ppm) or electrical conductivity (EC) in 
microsiemens per centimeter (p.S/cm). There are three sources of salts in the study area: 
(1) Water imported from the Sacramento-San Joaquin Delta; (2) soils; and (3) ground water. 
The imported water is of generally good quality; that is, its average salinity is less than 350 
ppm. But because of the large volume of such water, about 1,600,000 tons^ of salts are 
imported per year (D.G. Swain, 1990). 

1 Calculated by: Firm water supply imported annually (3,400,000 acre-feet) x salinity (350 ppm TDS) x con- 
version factor (0.00136) = 1,620,000 tons. 



30 



Figure 6 

AREAS OF SHALLOW GROUND WATER 
1987 



, Sacramento 




LEGENV 

''llli" "'I'" Edge of Valley Floor 

. — -'"^ General Study Area Boundary 
Depth to Shallow Ground Water 



to 5 feet 
5 to 10 feet 
10 to 20 feet 



Estero 
8ay 



Adapted from DWR.1987. 



31 



NOTE: Cross-sections shown on Figure 4. 



San 
Francisco I 



Figure 7 

SALINITY IN SHALLOW GROUND WATER 
Sampled between 1984 and 1989 

(Measured as Electrical Conductivity in microsiemens per centimeter [/iS/cm] ). 
, Sacramento ■., 



.jf 



Phtsburg'"' 



I, 
o 



%: 



\ 



1^ 



«$iS 



% 



^jteluiwie, 

•Stockton 

Stanisjaui^ 

Tuolumne 



%. 



Wk 



'%^ 



vAeii 



^. 



.'^G, 



^Q 



4i=. 



€^ 



% 






10 20 

I— J 1 l-_l 

MILES 



River/ 



^ 




\ 



LOCATION MAP 



li."'.B<in..O 



Monterey Bay 



IgiU Bancs ^, 



0' \„. 



CanW' 



RIVER^ 



Fresno 



*> 



River 



% 
^ 



LEG EN P 

' '"'"■■'""" Edge of Valley Floor 

— -"^^ General Study Area Boundary 



Insufficient data for analysis 
Less than 2500 /iS/cm 
2500 to 5000 iJS,lzm 
5000 to 10000 ^tS/cm 
10000 to 20000 /^/cm 
Greater tfian 20000 /jS/cm 



Say 






*••„ Gin 



• San Luis Obispo 




Ba^sfieldl 



32 



SJVDP 



Figure 8 

SELENIUM CONCENTRATIONS IN SHALLOW GROUND WATER 
Sampled between 1984 and 1989 



PiMsbuig ■ 



San 
Francisco \ 



. Sacramento v 







l^S 



ke!H!!l[!S; 



B/verj 



Stockton 



^er 



•^ 



MILES 



\ 



N 



LOCATION MAP 



Monterey Bay 



RIVER 



Fresno 



River 



Monterey 



I ''anochi 



»^ 



Cai 



intua CW 






.,KeltlcnHiMW Tulare Lakebed 



iMW "II" Edge of Valley Floor \s^ 

^-^.^^ General Study Area Boundary 


E5tero\ 
Bay \ 


• San Luis Obispo 




) 


insufficient data for analysis 
1 Less than 5 ppb 


J^^^ Bay^sfieldl^ 




^*Ama Vistay \ 


"j 5 to 50 ppb 


I ^~\ r^rn Lakebed 




■"" -^ 


50 to 200 ppb 


C'PfS^ 




Vk \J3«* 


] Greater ttian 200 ppb 





33 



SJVDP 



Figure 9 

BORON CONCENTRATIONS IN SHALLOW GROUND WATER 
Sampled between 1984 and 1989 




LEGEHV 

1 i\lli""ili'" Edge of Valley Floor 

<^~' General Study Area Boundary 

Insufficient data for analysis 

Less than 2 ppm 

2 to 4 ppm 

4 to 8 ppm 
l^^l Greater tfian 8 ppm 



34 



SJVDP 



Figure 10 

MOLYBDENUM CONCENTRATIONS IN SHALLOW GROUND WATER 
Sampled between 1984 and 1989 











Vx 


^ ^ Sacramento i^ 


r 


V 








4_ 




^C 


3>^ 


c~^ 


___- 


^ 








\ 




f X'^^ 


5 


9^ 


^— 




rl 


^y.-"" 


J 
3 


// 


/^^ ^okel'J'""^^ 




/ 




) Jp^ 


./L 


i^ 


cZ^^v 


V-^ ^>;^R/ver. 


\ 




/% 




> r^^ Pittsburg' 




i^*^^^Jo 




1 


/ 


% 


-v 


i V 






r\.. cU 


"\ X"^* Stockton 


\ 


i^ 




San / 

ancisco 1 


1 Y\ 






ip 


^^ Stanislfiii-^ 


%, 


/"^~w 


I 


y ^ 


h. 


» 






Tuolumne 
• — / 


-y 


^ 


I 


\ 






\ 


y^% 




O 


V 


^ 


^ 








\ 





Monterey Bay 



RIVER 



-^ 



10 20 


MILES 



^& 



\ 



N 



LOCATION MAP 



River 



Fresno 



Monterey 



Ca"' 



LEGEM d 

,,\\li,. niiH, E(jge of Valley Floor 

—^ — General Study Area Boundary 
Insufficient data for analysis 
Less than 20 ppb 
20 to 100 ppb 
100 to 1000 ppb 
Greater than 1000 ppb 



■v 


\^ 


^ 


,|KcllleimlVA rJWuiiiw/ \ 




Estero\ 
Say \ 


• San Luis 


Obispo 




'JW^na Visfa/ j 



35 



SJVDP 



Figure 11 

ARSENIC CONCENTRATIONS IN SHALLOW GROUND WATER 
Sampled between 1984 and 1989 







ft 


_ Saaamento v ] 


A/- 






\ 




j^^-^-'^'S^ 




■^ 








f x^ ^ 


^ 


y" - 




^ / 


^<! 






i/ 
y 


^ 


^ ryj^^ PiHsfcurg '"■•■.,.. 


m 


m^f"^^ 


^ 


^\ 


S: 


5>S 


I "'"<'/.. Cll 


^■C* Stockton "V 


/ 




San / 
Francisco \ 




I^s 




%n 




I 


^^A 


\ ^^{^ .-~^^2!!^^^ 


V 


l'^ 


I 


V H^ 






/" 


\ 




J 




^'^-fOvT 








1 










TV 


^ 


\ 


^IW^ 


% 




O 


\--\ 




1 n v^^^c) wv^ Banos* 


\ 





Monterey Bay 



I Monterey 



V 



RIVER 



10 20 

l_l I l_J 

MILES 



\ 



■%. 




Fresno 



N 



LOCATION MAP 



River 



^/ 



\ 



LE6EHd 

I '\»i"-'"'"' Edge of Valley Floor 

<«' General Study Area Boundary 

I Insufficient data for analysis 

I I Less than 50 ppb 
50 to 100 ppb 



•'^, 



^^^1 100 to 300 ppb 

I I Greater than 300 ppb 



\ 


\^ 


^ 


'■, City \T^ > \ 

<"■■■■-- %\ <^ 




Ester\ 








*J«^A/ 


Bay \ 


• San Luis 


Obispo 




■ — ^^\ ' ^ mm Lakebed 



36 



SJVDP 



Figure 12 

AQUIFER ZONES ABOVE THE CORCORAN CLAY WITH LESS 

THAN 1,250 ppm TOTAL DISSOLVED SOLIDS 

(Sampled between 1960 and 1989) 




\\ 






LEG EN d \ 




/ 


I iWli- "111" Edge of Valley Floor \^ 




\ 


<''"* General Study Area Boundary 


\ 




Aquifer Zone Thickness 


£s(ero\ 
Bay \ 




Less than 100 feet 


• San Luis Obispo 






100 to 200 feet 


^ 




\ 


200 to 300 feet 


1 






Greater than 300 feet 





Shallow ground water boundary 



37 



SJVDP 



A buildup of salts in the soil can adversely affect agricultural productivity. The arid soils on 
the westside San Joaquin Valley contain substantial amounts of naturally acquired soluble 
salts that can leach into the ground water below the root zone. These salts contribute heavily 
to the salinity of the soil solution and, subsequently, to the drainage water, if a field is 
drained. About half the soluble salts in the crop root zone are derived from the soil 
(CH2M Hill, 1988). Evapotranspiration increases the concentration of salts in the soil, and 
Use of irrigation return flows also further concentrates them. 




Ponds used to evaporate subsurface drainage water often cover several hundred acres, are generally 
divided into cells, and can evaporate about 4 feet of water per acre each year. 

The chemical forms of total dissolved solids (salts) found in subsurface agricultural drainage 
vary from region to region in the San Joaquin Valley. The composition of drainage water is 
largely dominated by sodium and sulfate, although chloride is dominant in some places. A 
U.S. Geological Survey study (Deverel, et al., 1984) described concentration ranges for these 
major substances in drainage water from the Coast Range alluvium, the basin trough, and the 
transitional basin rim. Salts are highest in the basin rim zone. Median concentration of 
sulfate ranged from 310 to 3,450 ppm, with a maximum of 65,000 ppm. Chloride varied from 
a median of 220 to 455 ppm, with a maximum of 16.000 ppm. Sodium ranged from a median 
concentration of 230 to 1,100 ppm in the three zones, with a maximum concentration of 
30,000 ppm. Other major substances are calcium, magnesium, potassium, and bicarbonate 
plus carbonate. Electrical conductivity (EC) ranges from a median of 1,900 to 6,055 jiS/cm in 



38 



the three zones, while the maximum observed value was 68,000 ^.S/cm. By comparison, the 
electrical conductivity of seawater is about 50,000 jiS/cm. 

High concentrations of nitrate with values greater than 70 ppm have also been observed in 
some areas. Nitrates are considered to have a dissolved salt source, although certain 
pollutant-type sources such as fertilizers and feedlots have also been documented. A 
potential public health hazard may exist if nitrates in public water supplies exceed 45 ppm. 
Nitrates and sulfates in drainage water also have been shown to hinder selenium removal in 
certain treatment processes (Hanna, et al., 1990). 

Extensive sampling and analyses by Federal and State scientists during the period 1984-1989 
have shown that pesticides are rarely detected in westside subsurface drainage water. 
However, pesticides have been observed in field irrigation runoff (tailwater), and com- 
mingling of tailwater and subsurface water does occur in parts of the valley (Gilliom and 
Clifton, 1987). 

Evaporation ponds are one of the most common means to dispose of subsurface drainage 
water in the southern San Joaquin Valley. High salinity in the ponds, entering either from 
outside sources or developing from evaporation, produces concentrations of salts that may 
cause environmental problems. The dominant minerals (salts) in the evaporation ponds are 
typically sodium sulfate and sodium chloride, mainly due to the composition of geologic 
formations contributing to subsurface drainage systems. Inflow TDS concentrations were 
observed to range from 2,500 to 65,000 ppm in one study (CVRWQCB, 1988c). 
Concentrations in the ponds affected by evaporation have been measured as high as 388,000 
ppm. (Seawater is about 31,000 ppm TDS.) During the evaporation-driven process of 
concentration, numerous physical, chemical, and biological processes affect the reactivity, 
solubility, and availability of trace element constituents in these high-salinity evaporation 
ponds (K.K. Tanji, in press). 

Trace Elements 

Toxic and potentially toxic trace elements occur naturally in some soils on the western side of 
the San Joaquin Valley, and they are leached into the shallow ground water during irrigation. 
These elements, originally found in the geologic formations of the Coast Ranges, can be 
mobilized, transported, and concentrated in irrigation drainage water. Another minor source 
of trace elements is imported irrigation water. 

Over the past several years, many studies have evaluated the chemical composition of 
agricultural drainage water. These studies, conducted by government agencies and other 
researchers, have produced evidence of the existence of a large group of trace elements or 
chemical substances that may be found at elevated concentrations at some time or place in 
irrigation drainage water. This group of elements or chemical constituents, called 
"substances of concern," comprises 29 substances (Table 4). Basically, these substances are 
of concern in the environment because of their actual or possible adverse effects on water 
quality, public health, agricultural productivity, and/or fish and wildlife. 



39 



Table 4. SUBSTANCES OF CONCERN 



Of Primary 


Of Probable 


Of Possible 


Of Possible 


Of LImrted 


Probably Not 
of Concprn 


Concern 


Concern 


Concern 


Concern 


Concern 


at Present 




Subject to future 


Elevated 


Little information 


Known toxic ele- 






California water- 


concentrations 


available 


ments in low 






quality objectives 


at some sites 




concentrations 




Selenium 


Cadmium 


Uranium 


Tellurium 


Lead 


Magnesium 


Boron 


Chromium 


Vanadium 


Antimony 


Silver 


Iron 


Molybdenum 


Copper 


Nitrates 


Lithium 


Mercury 


Barium 


Arsenic 


Manganese 




Germanium 




Aluminum 


Salts 


Nickel 
Zinc 




Bismuth 

Strontium 

Fluoride 

Beryllium 







Criteria used by the Drainage Program as evidence of primary concern include these factors: 
(1) The substance has been cited in State/Federal water-quality regulations (there are 
water-quality criteria affecting its concentration, use, and distribution); (2) it is known to 
cause toxicity and create other problems for fish and wildlife; and (3) it can become 
hazardous to other wildlife and to humans by accumulating in the food chain or by direct 
exposure to contaminated soils, sediments, air, or ground water and surface water. 

The trace elements of primary concern are selenium, boron, molybdenum, and arsenic, all of 
which occur naturally in westside soils. Arsenic is of concern primarily in the Tulare and 
Kern Subareas, where it has been observed in elevated concentrations in shallow ground 
water. In other locations, such as parts of Westlands Water District, concentrations of 
hexavalent chromium in shallow ground water have been observed above usual background 
levels. The State Water Resources Control Board and the Drainage Program have also 
identified salts as substances of primary concern. 

In addition, other elements for which the State Board eventually may establish site-specific 
water-quality criteria are cadmium, copper, manganese, nickel, and zinc (SWRCB, 1987). 
Samples from some evaporation ponds have shown high concentrations of uranium. Elevated 
concentrations of vanadium have also been found in some evaporation ponds. Other 
substances have also been measured in ongoing monitoring programs. These include 
nitrates, tellurium, mercury, antimony, germanium, bismuth, strontium, fluoride, beryllium, 
lead, magnesium, iron, aluminum, lithium, silver, and barium. In some instances, there is not 
enough information on the effects of these elements to establish them as substances of 
primary concern, and in others, the concentrations are not high enough to establish a definite 
level of concern. 

Selenium leads the four elements of primary concern, primarily because it is widely 
distributed in the study area and because of its proven and potential toxicity. Water and 
mudflows have transported the selenium to the valley in particulate and dissolved forms 
derived from the weathering and erosion of source rocks. Decades of irrigation have 



40 



transferred soluble selenium from the upper soils to the shallow ground water, where its 
highest concentrations occur generally along the edge of the valley trough in the lower parts 
of the Coast Range alluvial fans. 

Selenium concentrations in shallow ground water show a wide range of values. In the U.S. 
Geological Survey's study of three physiographic zones (Coast Range alluvium, the basin rim, 
and the basin trough) on the western side of the valley (Deverel, et al., 1984), values ranged 
from less than 1.0 part per billion (ppb) to 3,800 ppb, with a median concentration for all 
zones of 6.0 ppb. Water entering Kesterson Reservoir in the spring of 1984 had an average of 
385 ppb. To protect freshwater aquatic life, the Environmental Protection Agency recently 
established ambient water-quality criteria for selenium — 5.0 ppb for chronic toxicity and 
20 ppb for acute toxicity (USEPA, 1987). Saltwater limits are higher. The State Board has 
established a monthly mean objective for selenium of 5.0 ppb for a specific area of the San 
Joaquin River. 

Evaporation ponds can accumulate and concentrate trace elements that may be hazardous to 
wildlife, especially waterfowl and shore birds that use the ponds. A study of 22 ponds by the 
Central Valley Regional Water Quality Control Board indicates that trace-element 
concentrations vary widely (CVRWQCB, 1988c). Each of the four primary substances of 
concern (selenium, boron, molybdenum, and arsenic) occurs in high concentrations in one or 
more of the ponds. Selenium, for example, in these 22 ponds ranges from less than 1.0 ppb 
to 1,900 ppb, with a median value of 17 ppb. 

Elevated concentrations of boron (greater than 2.0 ppm) are found in parts of all the 
subareas under study, except the Northern Subarea. Although boron is essential to the 
nutrition of certain plants, concentrations in excess of 0.5 ppm are known to be harmful to 
some crops. For this reason, it is regarded primarily as an agricultural crop problem. The 
State Board established water-quality objectives for boron in the San Joaquin River that 
ranged from 0.8 to 1.3 ppm, depending on the time of year or whether it is a critically dry 
water year. The Regional Board's studies show that boron in evaporation ponds ranges from 
2.5 to 840 ppm, with a median concentration of 20 ppm. 

Molybdenum has been found in elevated concentrations (greater than 20 ppb) in various 
areas of the San Joaquin Valley, particularly in the Tulare and Kern subareas. Molybdenum 
in very low concentrations is essential to many plants and some mammal species. In high 
concentrations, it can be injurious to the growth of many kinds of plants. It can be toxic to 
livestock through bioaccumulation, particularly in ruminant animals (cattle and sheep). A 
technical committee of SWRCB recommended a 10-ppb criterion in water to protect 
agricultural uses. The EPA has not set any water-quality criteria for molybdenum. 
Molybdenum is an abundant element in evaporation ponds, ranging in concentration from 
7.0 to 7,775 ppb at the inlets to the ponds and 58 to 40,000 ppb in the ponds. Few studies 
have been performed to assess the potential consequences of elevated dietary molybdenum in 
humans. 

Arsenic is a known toxicant that has been shown to become concentrated at relatively high 
levels in evaporation ponds in the Tulare Basin. Arsenic values in evaporation ponds range 
from 2.0 to 900 ppb in the inlets to the ponds and 1.0 to 13,000 ppb in the ponds. 
Occurrences in other parts of the San Joaquin Valley are not as frequent, nor are the levels as 



41 



high, on the average. Certain chemical forms of inorganic arsenic are suspected human 
carcinogens. The EPA has set 50 ppb as the current maximum contaminant level for arsenic 
compounds in drinking water and established 190 ppb as the water-quality criterion for 
freshwater aquatic life. 

Uranium was not one of the elements of concern studied in earlier evaluations of 
drainage-water constituents. However, the presence of elevated concentrations of uranium in 
Tulare Basin evaporation ponds has been documented (CVRWQCB, 1988b). These ranged 
from 30 to 11,000 ppb in studies conducted in 1987-88. The mean concentration for all pond 
samples was 675 ppb, while the mean concentration in the inflow samples of the three basins 
studied was 280 ppb. Over 60 percent of the evaporation pond area exceeded a Canadian 
marine water-quality objective of 500 ppb uranium. At the present time, there is no 
information regarding the role uranium may play in the toxicity problems of the evaporation 
ponds. In 1988-89, the USGS studied the occurrence of uranium in shallow ground water in 
parts of the Tulare Subarea. Results have not yet been published. 

The toxicity of drainage-water constituents is influenced by their chemical interaction with 
other substances. The understanding of these interactions is limited. In addition to the 
independent effects of trace elements, antagonistic or synergistic interactions may occur 
among various constituents. 

The list of substances that may be of concern in drainage water is not final at this time. 
Certain other substances not now listed have occasionally been detected in drainage-water 
samples or in water influenced by subsurface drainage. Future studies and continued 
monitoring may produce data that will indicate whether certain chemicals not presently 
thought to be important will have to be more thoroughly appraised. 

DRAINAGE-WATER TREATMENT AND REUSE 

At the beginning of the Drainage Program, major effort was focused on treatment of drainage 
water to make it environmentally acceptable and/or reusable. Selenium became the principal 
concern in those efforts because of confirmed associations between adverse effects on wildlife 
and the presence of selenium in drainage water. Unlike other substances of primary concern, 
no practical treatment method for selenium removal was known to exist. 

Treatment Processes 

Problems at Kesterson Reservoir generated about 150 ideas and suggestions that were 
submitted to the Drainage Program. Many were oriented toward drainage water treatment 
and many were research proposals. The staff initially screened all the ideas and submitted 
about 30 of them to the Program's Treatment and Disposal Subcommittee for evaluation and 
final screening. The subcommittee further narrowed the choices, but because of funding 
limitations, only the most promising methods were pursued. 

The Drainage Program investigated the 11 processes listed in Table 5 but did not fund all the 
developmental research. Others (for example, Westlands Water District, Panoche Drainage 
District, and the California Department of Water Resources) also funded research on 
treatment processes. Chapter 3 of the Drainage Program's Preliminary Planning Alternatives 



42 



summarized the various treatment processes investigated. Technical reports on the various 
treatment processes have been prepared and a review and evaluation of each treatment 
process has been completed (Hanna, et al., 1990). 

Anaerobic-Bacterial Process 

This process was tested by EPOC AG in a small-scale pilot plant, using a biological reactor 
(including upflow fixed-film beds, fluidized beds, and sludge blanket reactors) and 
microfiltration. EPOC AG concluded in 1987 that the biological process is a practical and 
proven method for treatment of selenium-laden drainage. 

The optimum treatment train was sludge blanket to fluidized bed to microfiltration. The 
process lowered selenium levels in the feedwater from 300 to 500 ppb down to 12 to 40 ppb, 
and thence to below 5.0 ppb with ion exchange "polishing." However, interpretation of the 
data generated by the EPOC AG pilot plant is complicated by the ever-changing nature of 
the plant's operation. It operated under field conditions, with wide changes in drainage water 
quality and diurnal and seasonal temperature variation, as well as in other significant 
parameters. 




The anaerobic-bacterial process of removing selenium from drainage water was tested 
in this small plant near Mendota in 1986 and 1987. 

Laboratory-scale research at the University of California, Davis, was conducted as foUowup 
to the work by EPOC AG, mainly to determine the mechanisms of selenium removal in the 
anaerobic-bacterial process (Schroeder, et al., 1989). It was determined from studies using 
sequencing batch reactors and fluidized bed reactors that selenate reduction occurred 
simultaneously with nitrate reduction. It was theorized that selenate reduction was primarily 
a detoxification mechanism, rather than a respiratory process. In respiration, nitrate would 



43 



be used before selenate. The researchers postulated that the bacteria are detoxifying their 
environment of high concentrations of selenate, while simultaneously respiring on nitrate. 

Facultative-Bacterial Process 

This process was studied in the laboratory at the U.S. Bureau of Mines Research Center in 
Salt Lake City. Utah (Altringer, et al., 1987). Selenium was reduced from selenate to selenite. 
using facultative bacteria that can live with or without oxygen, and precipitated from solution 
in elemental form. This study also demonstrated that the mechanism of selenium removal is 
influenced by nutrient addition, oxygen supply, and temperature. Aerobic conditions 
encouraged bacterial growth, but selenate reduction was enhanced when the air supply was 
restricted. 

Table 5. STATUS OF DRAINAGE-WATER TREATMENT PROCESSES 
TO REMOVE OR IMMOBILIZE SELENIUM 



Process 


Research 


Development 


Testing and 
Evaluation 


Biological 








Anaerobic-bacterial 






X 


Facultative-bacterial 


X 






Microalgal-bacterial 
Microbial volatilization in 


X 


X 




evaporation pond water 
Microbial volatilization 






X 


from soils and sediments 








Physical and Chemical 








Geochemical immobilization 


X 






Iron filings 

Ferrous hydroxide 

Ion exchange 

Reverse osmosis to remove 


X 


X 


X 
X 


salts and other contaminants 








Generate electrical energy and 
heat for desalination with 






X 


a cogeneration process 









In many respects, the mechanism of selenium removal in this process appears similar to that 
occurring in the anaerobic-bacterial and microalgal-bacterial processes. It involves reducing 
selenate to selenite to elemental selenium, which accumulates in the biological sludge of the 
reactors. The same bacteria genus contained in EPOC AG's anoxic fixed-film reactor sludge 
was shown in this study to reduce selenate first and adapt well under high selenium 
concentrations. The study also demonstrated that optimal selenate reduction by facultative 
bacteria occurs under anoxic conditions. 



44 



Microalgal-Bacterial Process 

This process was investigated by the University of California at Berkeley (Oswald, et al., 
1990). The process is based on the principle that soluble selenate can be reduced by 
microorganisms to less-soluble selenite and elemental selenium in an anoxic sludge blanket 
reactor. While elemental selenium settles and accumulates in the reactor sludge, selenite 
suspended in the reactor effluent can be precipitated with ferric chloride and removed by a 
dissolved air flotation system. 

The carbon source for the biological reactor is algae cultivated in high-rate algal ponds fed by 
drainage water. If drainage nitrate levels are above that which can be assimilated by pond 
algae, a denitrification reactor is added upstream from the selenate-reducing reactor. 

The researchers believe that excess algae can be fermented to produce methane for power 
generation, carbon dioxide can be recycled for pH control in the algae ponds, and the 
digested sludge can be diverted to the biological reactors to supplement the algal feed. 
Although the field tests did not reach steady-state conditions, the process showed promise of 
greater than 95-percent removal of selenium. 

Microbial Volatilization of Selenium In Evaporation Pond Water 

This process was studied primarily as an in-situ means to maintain selenium levels in 
evaporation ponds below the hazardous waste criterion of 1.0 ppm. It was not intended to 
meet the more stringent criteria for wildlife protection. 

Investigators in 1990 reported that compounds high in protein, such as casein, dramatically 
accelerate biological removal of selenium, but substantial amounts of the compounds are 
apparently required, probably creating eutrophic ponds (Frankenburger and 
Thompson-Eagle, 1989). Bacteria were identified as the predominant active selenium 
methylators in pond water. The researchers conclude that further studies are needed to 
determine whether protein-mediated methylation can be optimized through the addition of 
coenzymes, methyl donors, and aeration, as well as through the addition of specific microbial 
inoculants. They further conclude that it may be possible to design a pilot bioreactor to test 
selenium removal. This technique lags in developmental efforts. 

Microbial Volatilization of Selenium from Soils and Sediments 

This process is being investigated by researchers from the University of California at 
Riverside to determine whether biomethylation of selenium could be accelerated and used as 
a bioremediation technique to remove selenium from Kesterson Reservoir and the San Luis 
Drain (Frankenburger and Karlson, 1989). Indigenous soil fungi are the primary organisms 
that volatilize the selenium, and dimethylselenide is the primary gaseous end product. The 
process was field-tested, following treatment methods in which different additives were used. 
This work was done at Kesterson Reservoir, on San Luis Drain sediments, and at a Peck 
Ranch evaporation pond. All treatments included moisture application and rototilling. 

At Kesterson Pond 4, where selenium concentration in the upper 6 inches of soil averaged 
about 39 milligrams per kilogram, treatment using citrus peel -I- ammonium nitrate + zinc 
sulfate and treatment using casein were most effective. The average emission rate with the 
citrus peel treatment was about 40 times greater than it was for background level. It was 



45 



estimated that the treatment would require about seven years to achieve the cleanup goal of 
4 mg/kg from the initial concentration of 39 mg/kg. The selenium volatilization rate is highly 
temperature-dependent, with the highest rates occurring in the late spring and summer 
months. 

Geochemical Immobilization 

A physical/chemical attenuation process to transform and immobilize selenium in place was 
investigated by UC Riverside researchers (Neal and Sposito, 1988). The study was conducted 
to identify the pertinent variables in an irrigated soils system designed to implement 
management techniques that would control the eventual fate of selenium by immobilizing it in 
the soil profile. The researchers concluded that the chemical form in which selenium exists in 
the aqueous phase governs the applicability of this process. If, as in the soils of the western 
San Joaquin Valley, selenate predominates, farm level management practices to achieve 
physical/chemical attenuation would have little success in immobilizing selenium. 




Panoche Water District Is testing ttie removal of selenium by passing drainage water 
through a bed of iron filings in the bottom of this basin. 



46 



Iron Filings 

In 1985, Harza Engineering Company tested its patented heavy metals adsorption process for 
removing selenium from drainage water at Panoche Drainage District. In this process, heavy 
and toxic metals are adsorbed onto iron filings and removed from solution as drainage water 
flows through a bed of "activated" iron filings. Before the beds are exhausted, the iron filings 
are replaced, activated, and returned online. The spent material can be disposed of at 
landfills or recycled to the metal-working industry. 

A problem arose in initial field testing. The filings solidified and clogged the bed. A study 
was conducted at the University of Wisconsin, Madison, to determine the mechanism by 
which selenium is removed and the selenium specie formed to effect removal (Harza, 1989). 
It was concluded that selenium is removed by chemical adsorption on iron oxyhydroxide 
surfaces at an orange-brown layer of iron filings, where drainage water enters the column. 
Before the oxyhydroxide layer forms, selenium can be removed throughout the iron-filing bed 
by physical adsorption. There is still uncertainty regarding the exact mechanism whereby 
selenium is removed in the Harza process. 

The study did not conclusively define the cause of the bed-clogging problem. The formation 
of magnetite (Fe304), a ferromagnetic solid that restricts flow, was suggested as a possible 
cause. Other possibilities, such as calcite precipitation, were also suggested, but 
bed-hardening also occurred in columns with selenate-spiked distilled water. 

Pilot tests are presently being conducted in treatment ponds at Panoche Drainage District. 
Information from these tests should help to better evaluate the effectiveness and cost of this 
process. 

Ferrous Hydroxide 

Studies of this process were conducted by staff of the U.S. Bureau of Reclamation's Denver 
Office (Rowley, et al., 1990). The process is based on a reaction in which ferrous hydroxide 
reduces selenate to elemental selenium. The reaction rate depends on pH, for which the 
optimum range is 8 to 10. Temperature affects the rate of selenate removal by about 
doubling the rate for each 10° C increase. Most of the tests were conducted at 20° C, the 
approximate average temperature of drainage water. 

The reaction time for selenate removal is inversely proportional to the ferrous hydroxide 
concentration, which was commonly used in the range of 2.5 to 20 millimoles per liter. The 
reaction times were very short (99-percent selenate removal in less than one minute) when 
deionized water was used for testing, but substantially longer times were required when 
drainage water was used. Field tests near Mendota resulted in 90-percent selenate removal 
after four hours. 

It was concluded that high concentrations of bicarbonate would decrease the reaction rate by 
half, while high concentrations of nitrate would reduce the reaction rate by a factor of 5. If 
high concentrations of both ions were present, the initial rate of reaction would be reduced 
by a factor of 17. Although oxygen does not appear to affect the rate of selenate removal, it 
oxidizes about 1.6 millimoles per liter of ferrous hydroxide if the water is saturated at 20° C. 



47 



Ion Exchange 

Use of selenium-selected resins to remove selenium was investigated in laboratory tests on 
drainage-water samples (Boyle, 1988). Two strong anion-base resins, both similar to 
commercial resins, showed selectivity for the selenate ion over the sulfate ion. The 
investigators concluded that this indicated ion exchange is a promising method. However, 
studies have not been conducted to demonstrate field-scale reliability and costs. 

Reverse Osmosis to Remove Salts and Contaminants 

This is a versatile, proven treatment process capable of removing salts, as well as 
trace-element contaminants, but it is also much more costly than the other treatment 
processes. The California Department of Water Resources operated a drainage-water 
desalting demonstration plant at Los Banos from the fall of 1983 to August 1986. DWR 
concluded that additional work is required on the pretreatment system to establish the 
feasibility of a drainage water desalting facility. DWR has issued a report on the 
pretreatment systems tested (DWR, 1986), and reports on other components of the project 
(ion exchange and reverse osmosis) are being completed. 

Cogeneration 

This process uses waste heat from the thermal generation of energy to evaporate drainage 
water. However, from review of a cogeneration study completed in 1989 (RMI, 1989), the 
Drainage Program concluded that cogeneration using natural gas fuel is not promising for 
evaporation of unconcentrated drainage water because of the high cost and the relatively 
small amount of drainage water treated (about 7,500 acre-feet annually in conjunction with a 
100-megawatt powerplant). 

Westlands Water District, with Drainage Program participation, conducted a preliminary 
study of burning salt-tolerant agroforest biomass to evaporate drainage water concentrated 
by agroforestry crops (RMI, 1990). RMI concluded that wood fuel cannot be economically 
substituted for natural gas to fuel a cogeneration component of a drainage water evaporation 
plant. 

Future of Treatment Processes 

The implementation of any drainage water treatment process is burdened largely by three 
major items: (1) The need to keep costs low and affordable for agricultural application, (2) 
the stringent performance criteria imposed by the need to reduce selenium to extremely low 
concentrations (less than 5 ppb) in receiving water, and (3) the early developmental status of 
technology for selenium removal from drainage water. Because selenium-removal technology, 
unlike reverse-osmosis desalting, has not progressed to large-scale application, it is premature 
to recommend a specific treatment process at this time. However, selenium removal research 
indicates that treatment may be a viable drainage management strategy under certain 
conditions and, therefore, further treatment research is justified. 

Because the Drainage Program wanted to encourage the search for an economical way to 
remove selenium from drainage water, its Interagency Technical Advisory Committee's 
Treatment and Disposal Subcommittee was asked for advice on which process to pursue. 
The subcommittee recommended support of a 30,000-gallon-per-day demonstration plant 
using the anaerobic-bacterial process field-tested by EPOC AG. The Department of Water 



48 



Resources intends to fund the demonstration plant in 1990, with support from the U.S. 
Bureau of Reclamation. 

In the EPOC AG field-pilot tests, selenium in drainage water at a concentration of 300 to 
550 ppb was lowered to about 10 to 40 ppb after microfiltration and to less than 10 ppb after 
polishing in boron selective ion-exchange resins. EPOC AG has reported estimated 
treatment costs for a 1-million-gallon-per-day prototype plant of about $76 per acre-foot to 
construct (capital at 4 percent, with 20-year plant life) and $148 per acre-foot to operate. 
Total product cost would be about $224 per acre-foot. It was also estimated that, for a 
10-mgd plant, the total unit treatment cost would decline to about $145 to $175 per acre-foot, 
depending on the availability and cost of a carbon source. These estimates did not include 
waste-stream disposal costs. 

A study sponsored by the Drainage Program reviewed and evaluated each treatment process 
investigated, and, when cost estimates were available, adjusted them on a common basis 
(Hanna, et al., 1990). Revisions of EPOC AG's cost estimates were based on increases in the 
interest rate from 4 percent to 9% percent, electricity rates from $0,045 to $0.08 per 
kilowatt-hour, labor costs from $28,470 to $40,000 per person per year, and capital costs by 35 
percent. Added to these were replacement costs and 27 percent for overhead and profit. 
Those changes raised the estimated total product cost from $224 to $456 per acre-foot for a 
1-mgd plant and from $175 to $301 for a 10-mgd plant. Neither estimate includes costs of 
polishing to lower selenium levels to less than 10 ppb, or of waste-stream disposal. 

Reuse 

If drainage water could be economically reused, it would be a resource, not a waste disposal 
problem. The Drainage Program funded investigations of the reuse of drainage water for 
irrigation of salt-tolerant trees and halophytes. It also reviewed the results of reuse 
investigations conducted by others. These mainly concerned the use of drainage water in 
powerplant cooling, temperature-gradient solar ponds, aquaculture, salt and mineral recovery 
and marketing, and agriculture. 

There are no current plans for siting major thermal powerplants in the valley and hence no 
significant demands for drainage water for cooling. Treatment costs would be substantial to 
produce drainage water acceptable for powerplant cooling. Possibilities exist, though, that 
energy-producing solar ponds could be used in drainage water management because of the 
increasing demand for, and cost of, electrical energy and because of growing concern for air 
quality in California. Both the Bureau of Reclamation and the Department of Water 
Resources are pursuing further solar pond investigations. 

The potential for both salt and mineral recovery and aquacultural reuse rests largely with the 
marketability of the products — primarily sodium sulfate, in the case of salt recovery, and 
the products grown in drainage water, in the case of aquaculture. Such markets do not 
appear promising at present because sources are available elsewhere, but these are subject to 
change in the future. 

Reuse of drainage water by irrigating salt-tolerant crops or by blending with normal irrigation 
supplies are the only reuse options that appear promising at this time. 



49 



AGRICULTURAL ECONOMY 

Agriculture is the mainstay of the economy of the westside San Joaquin Valley. Knowledge of 
the agricultural economy and the way in which it relates to the region, the State, and the 
nation are important to understanding and planning for management of the drainage 
problem. The information that follows is from the Census of Agriculture reports (1978, 1982, 
1987), Census of Manufacture reports (1978, 1982, 1983, and 1985), and data from the 
California Department of Food and Agriculture and a commercial agricultural lending 
agency, as presented in a report sponsored by the Drainage Program (Archibald, 1990). 
Additional information is available in the full report. 

The Contribution of Agriculture 

California leads the nation in the market value of agricultural production. In 1987, 
California's total value of agricultural output was $13.92 billion; this represented 10.2 percent 
of the total $136 billion U.S. agricultural production. Of the California total, $9.27 billion was 
contributed by crops and $4.65 billion by livestock, poultry, and related products. 

The San Joaquin Valley is California's largest single agricultural area, contributing $6.82 
billion (49 percent) of the State's total agricultural output. Crops accounted for $4.45 billion 
(65 percent), and livestock and livestock products contributed $2.37 billion (35 percent). 
Figure 13 provides a breakdown of the total crop production value in the San Joaquin Valley. 

Of the total value of crop production in the U.S., 50.9 percent was derived from irrigated land 
and 49.1 percent from nonirrigated land. In contrast, only 19.9 percent of the value of 
livestock and livestock products was derived from irrigated land, while 80.1 percent was 



Figure 13. SAN JOAQUIN VALLEY TOTAL CROP PRODUCTION VALUE 
(Value = $4.45 billion in 1987) 



10% 



10% 




51% 



fruits and nuts 
cotton 



s!!vj vegetables 

■ hay 

I I grain 

I I miscellaneous 



50 



contributed by nonirrigated land. Irrigated land in California accounted for about 45 percent 
of total U.S. crop production on irrigated land, and the San Joaquin Valley alone contributed 
about 21 percent of the U.S. total. 

The importance of agriculture to the economy of California can be estimated by examining 
employment statistics. Statewide in 1987, agriculturally induced employment accounted for at 
least 17.3 percent of employment and 18.5 percent of total payroll. Within the San Joaquin 
Valley, these categories were 48.6 and 54.2 percent, respectively. Figure 14 shows 
agriculturally induced employment in the San Joaquin Valley. 

Figure 14. AGRICULTURALLY INDUCED EMPLOYMENT IN THE 
SAN JOAQUIN VALLEY BY COUNTY, 1987 



^^ Fresno 

I I San Joaquin 

P'H Stanislaus 

!. 1, 1, 

'SS Kern 

HH Kings 



10.5% 



9.5% 




30% 



j I Madera 



19.5% 



20.5% 



Merced 



In 1987, agriculturally induced employment in each valley county was even more striking, 
representing more than 50 percent of employment in Kings, Madera, Merced, and Stanislaus 
counties and about 50 percent in Fresno, San Joaquin, and Tulare counties. In Kern County, 
agriculture accounted for only 20 percent of employment, reflecting the development and 
growing importance of other industries, such as petroleum. 

Exports 

California also leads the nation in agricultural export value. The State's export value declined 
during the 1980s, as did U.S. export value, but the State's value recovered significantly by 
1987. The leading single export commodity from California is cotton lint. Figure 15 shows a 
breakdown of the value of California commodity exports. In 1987, 62 percent of California's 
cotton output was exported. This accounted for nearly half the value of U.S. cotton exports. 
About 60 percent of the State's almond crop and 45 percent of the walnut crop were 
exported. This was the entire amount of U.S. exports of these two crops. 

Given these levels of exports, an estimated 1.76 million acres of California cropland were 
dedicated to producing for export markets in 1987. Cotton dominates exports in terms of 
land use. In 1987, production from 710,000 acres of cotton was required to meet California's 



51 



Figure 15. SHARE OF CALIFORNIA COMMODITY 
EXPORTS, BY VALUE, 1987 



42% 




18% 



cotton lint 

almonds and walnuts 
^1 major tree fruits and grapes 
I I meat and meat products 
I I other commodities 



export market. Of that area, 682,000 acres were in the San Joaquin Valley, and 450,000 of 
those acres are on the valley's western side. The rise in incomes in countries importing 
agricultural products from California favors growth in higher value export crops, such as 
fruits, nuts, and beef. For the 1990s, based on expectations of income and population growth 
in importing countries, the U.S. Department of Agriculture projects a 3-percent annual 
growth rate for agricultural exports, led by growth in high-value products. Food grain exports 
are not expected to grow as fast as feed grain exports, because importing countries are 
increasing their domestic meat production and must import feed grains. 

Land Use 

Total California farmland in 1987 was 30.6 million acres, with about one-third (10.5 million 
acres) in the San Joaquin Valley. Farmland on the western side of the valley accounts for 
one-third (3.4 million acres) of the valley total. About 7.5 million acres of cropland are 
irrigated, with irrigated pasture accounting for only 5 percent of the total. Over half (57 
percent) of the State's irrigated cropland is in the valley, and 40 percent of this is on the 
western side. Together, the Westlands, Tulare, and Kern Subareas account for more than 75 
percent of westside irrigated cropland. 

California farmland as a whole declined 2.3 percent from 1982 to 1987, a drop that was 
consistent with the national pattern, which declined 2.26 percent in the same period. For the 
valley, the decline was 3.0 percent; on the western side, it was 11 percent. 

A partial explanation for the decline of irrigated westside cropland is the acreage enrolled in 
the Federal Commodity Acreage Reduction Program and the Conservation Reserve Program. 
Idled cropland in the valley increased 125 percent from 1982 to 1987, or 13.4 percent of total 
irrigated cropland in 1987. Land under the Acreage Reduction Program increased 256 
percent from 1982 to 1987, to a total of 7.1 percent. Land set aside under the Conservation 



52 



Reserve Program for the valley as a whole was less then 1 percent of irrigated land. Drought 
conditions in 1987 also help explain the reduction in irrigated acreage. 

Forty-three percent of irrigated cropland on the western side of the San Joaquin Valley was in 
cotton in 1987. In the five subareas, the share of cropland in cotton ranged from 2.1 percent 
in the Northern Subarea to 52.2 percent in the Westlands Subarea (Figure 16). The cotton 
shares for the Kern, Tulare, and Grasslands subareas are 51.0, 49.5, and 34.6 percent, 
respectively. Other field crops, including feed grains, hay, wheat, sugar beets, dry beans, 
oilseeds, and rice, accounted for 34.3 percent of the valley's cropland and 38.4 percent of the 
westside cropland in 1987. The shares of cropland in these field crops ranged from 28.7 
percent in the Westlands Subarea to 51.9 percent in the Northern Subarea. Most dry beans 
have been grown in the Northern Subarea; most sugar beets, in the Northern and Grasslands 
subareas; and most oilseeds, in the Tulare Subarea. Conversely, hay has been grown 
throughout the west side, but minimally in the Westlands Subarea. Cotton is minimal in the 
Northern Subarea, as is wheat in the Grasslands Subarea. 

In 1987, fruit and nut acreage represented 8.3 percent of cropland on the western side and 
33.4 percent in the San Joaquin Valley as a whole (Figure 16). Together, almonds, walnuts, 
and apricots accounted for 92 and 86 percent of tree and vineyard cropland in the Northern 
and Grasslands subareas, respectively. 

In 1987, vegetables accounted for 10.3 percent of cropland on the western side, up from 7.7 
percent in 1982 and 7.3 percent in 1978. This represented an increase of 17,000 acres during 
the 10-year period. The share of cropland in vegetables ranged among the subareas from a 
high of 25.8 percent in the Northern Subarea to a low of 2.8 percent in the Tulare Subarea. 
Westlands Water District, which makes up most of the Westlands Subarea, had the greatest 
vegetable acreage, withl40,868 acres (Westlands Water District, 1988). Tomatoes, cantaloupes, 
lettuce, romaine, and dry onions occupied about 62 percent of land planted to vegetables in the 
valley. Tomatoes were the dominant crop, with 36 percent of the vegetable acreage. 

Production Expenses 

The western side of the San Joaquin Valley accounted for 29 percent of total valley 
agricultural production expenses in 1987. Given that the westside share of irrigated cropland 
is 40 percent, this indicates lower per-acre expenses for the western side than for the 
remainder of the valley. This could reflect a combination of a greater ratio of field and row 
crops to trees and vines on the western side and some economies of scale associated with 
large operations. Labor expenditures exceeded 20 percent of the total, followed by chemicals 
and machinery (including equipment), each at 10 percent, and energy at 6 percent. The 
shares of expenditures for labor, interest, and property taxes are lower than for the rest of the 
valley. Westside growers, however, dedicate a larger fraction of their production expenses to 
machinery, energy, chemicals, and irrigation water. In the subareas, cash rents per acre 
appear to decline as a proportion of total expenditures from north to south. The proportion 
of expenses in the form of interest payments was greater in the Northern Subarea, reflecting 
higher land values and per-acre investments in orchards. Energy expenditures in the Tulare 
and Kern Subareas were greater in proportion to other expenses than in other areas, 
reflecting the greater dependence on pumped ground water as an irrigation supply. 



53 



Westside land values have followed the national pattern, increasing from 1970 to the early 
1980s and then declining, with some recent evidence of recovery. Westside land prices are 
about five times the national average and are highest in the Northern Subarea, where 
orchards are prevalent. 



60 



50 



40 



Figure 16. IRRIGATED CROPLAND IN COTTON, 
FRUITS, AND NUTS, BY SUBAREA - 1987 



c 
m 

o. 
o 



re 
O) 



■S' 30 



c 
a) 
u 

a. 



20 



10 



Y//\ Fruits and nuts 
^^M, Cotton 





YZA 





Northern 



Grasslands 



Westlands 



Tulare 



Kern 



Farm Structure 

Farms are fewer but substantially larger on the western side than in the rest of the valley. 
Average farm size in the principal study area was about 500 acres in 1987, while the average 
for the rest of the valley was about 100 acres. Farms in the Westlands Subarea averaged 
1,100 acres in 1987; in the Tulare and Kern subareas, 500+ acres; in the Grasslands Subarea, 
400 + acres; and in the Northern Subarea, 200 acres. 

Farm tenure types fall into three classifications: (1) Full owners, who operate only the land 
they own; (2) part owners, who operate farmland they own, as well as land they rent; and 
(3) tenants, who operate only land they rent (Figure 17). Full ownership as a percentage of all 
forms of land tenure on the western side exceeded 50 percent in all subareas, except in 
Westlands, where it was 44 percent. 

Farm operations are also divided into three basic types of management structures: 
corporations, partnerships, and individual or family owners. Corporations are further 
divided into three groups: family-held; other-than-family-held; and others, including 
cooperatives. In 1987, individual owners and family corporations together accounted for 76.3 
percent of the farms on the westside San Joaquin Valley. In the Northern and Grasslands 
Subareas, corporations accounted for less than 1 percent of farms and less than 2 percent in 



54 



Figure 17. PERCENT OF FARMS BY TENURE OF OPERATOR, 
WESTSIDE SAN JOAQUIN VALLEY, 1987 



26% 




full owners 

I I part owners 

I I tenants 



each of the other subareas. All subareas had more than 70 percent of farms under individual 
ownership or in family corporations. 

Less than 0.5 percent of farmland in the Northern and Grasslands Subareas was owned by 
corporations. During the 10-year period, 1978-1987. the portion of land owned by 
corporations in the Westlands and Kern Subareas increased from 6 percent to 8 percent and 
from 7 percent to 8 percent, respectively. In the Tulare Subarea, the portion increased from 7 
percent to 16 percent. During the same period, land owned by partnerships in the 
Grasslands and Kern Subareas increased from 32 percent to 40 percent and from 35 percent 
to 40 percent, respectively. In the Westlands Subarea, the portion increased from 28 percent 
to 34 percent, while in the Tulare Subarea it increased from 25 percent to 35 percent. Only 
the Northern Subarea reported a decrease in land owned by partnerships during this 
period — from 38 percent to 36 percent. 

Federal Agricultural Programs 

Commodity Credit Corporation (CCC) payments to farm operators include loans for corn, 
wheat, sorghum, barley, oats, cotton, rye, rice, and honey. Government payments include 
deficiency payments, paid diversions, soil conservation reserve payments, payments from the 
Dairy Termination Program, other conservation programs, and other Federal farm programs 
under which payments are made directly to the farm operator. In 1987, CCC and other 
government payments to U.S. farms totaled $17.9 billion; $570 million was for loans and the 
remainder for payments. California received $69.1 million in CCC loans and $238 million for 
government payments. Total CCC payments for the San Joaquin Valley were $17 million, 
amounting to 28 percent of California payments. The valley received $126 million in 
government payments, or 53 percent of the State total. CCC loans to the western side for all 
program crops totaled $11.7 million. 



55 



Cotton was the most important source of CCC payments (83.6 percent) on the western side. 
In the Kern Subarea, 97 percent of CCC loan payments was for cotton, and the Grasslands 
and Westlands subareas received 75 and 84 percent, respectively, for cotton. The Northern 
Subarea received almost 40 percent of its CCC payments for corn, almost 50 percent for rice, 
and the balance for wheat. Feed-grain payments were negligible in the other subareas. 

While more than 25 percent of U.S. cotton farms participate in the CCC loan program, only 
10 percent do so on the western side of the valley and in the State. In 1987. the Grasslands 
Subarea accounted for 13.8 percent of the westside acreage in program crops, but farmers in 
the subarea received 23 percent of the CCC loans. The Westlands Subarea had 27.2 percent 
of the acreage in program crops and received 33.1 percent of the payments. The Kern 
Subarea had about 25 percent of the acreage and CCC receipts. The Tulare Subarea had 
32.8 percent of the acreage and 18.3 percent of loan payments. 

In 1987, westside farms received 0.6 percent of total U.S. payments and CCC loans to all 
farms, 2.5 percent of payments and loans to farms with any land irrigated, and 7.3 percent of 
payments and loans to irrigated farms. The San Joaquin Valley as a whole contributed 
21.3 percent of the value of U.S. agricultural output from irrigated farms and received 
10.5 percent of government payments to irrigated farms. 

FISH AND WILDLIFE RESOURCES 

[Data, references, and analyses supporting the information included in this 
section can be found in the Drainage Program's 1989 report. Preliminary 
Planning Alternatives./ 

Habitat Losses and Population Declines 

Long ago. seasonal flooding of large areas of the San Joaquin Valley floor created a 
patchwork of aquatic, wetland, riparian forest, and valley oak savannah habitats. 
Surrounding these overflow lands were large areas of California prairie and San Joaquin 
saltbush. In the southern part of the valley, Tulare Lake and four smaller lakes were 
interconnected by a vast network of sloughs, riparian forests, and wetlands. On the average, 
during the past few thousand years, all five lakes in the Tulare Basin covered a total of about 
516,000 to 625,000 acres, or about 800 to 1.000 square miles. 

The diversity of habitats in the valley supported large populations of resident and migratory 
species of fish and wildlife. Before the region was settled, the year-round native plant and 
animal life in the Tulare Basin was so abundant that it supported the densest population of 
native Americans on the North American continent that was not engaged in agriculture. 
During the late 1800s, enormous numbers of waterfowl and fur-bearing mammals were 
commercially harvested throughout the San Joaquin Valley, and Tulare Lake supported a 
small commercial fishery for western pond turtles and native minnows. 

Widespread development of agricultural lands, draining of the once-extensive lakes, 
drastically reduced instream flows, and declining water quality have taken a substantial toll 
on the native aquatic, wetland, riparian, and terrestrial habitats of the San Joaquin Valley. 
The present acreage of natural freshwater lakes on the valley floor is less than 1 percent of 



56 




Migrating ducks rising from a pond in wetlands of the Grasslands Subarea on the Pacific Flyway. 

the historic extent. Current acreages of wetland and riparian habitats are less than 15 
percent and about 7 percent, respectively, of their historic extent. San Joaquin saltbush 
habitat now occupies less than 7 percent of its historic acreage. Such drastic reductions of 
these habitats have caused the decline of many species of plants and animals endemic to the 
valley. Several species that once occurred in the valley no longer exist there or have become 
extinct, and 29 others are listed as endangered by the Federal or State governments. 

Water Supplies and Needs 

About 200,000 acres of public and private land in the San Joaquin Valley are managed 
primarily for the benefit of fish and wildlife. These areas need over 400.000 acre-feet per year 
of fresh water to satisfy optimum management needs. Reliable firm supplies of fresh water 
for these areas currently total about 30 percent of needs. 

At present, about 4.7 million acres of irrigated agricultural land in the San Joaquin Valley 
receive about 17.6 million acre-feet per year of irrigation water. Until recently, surface and 
subsurface agricultural drainage from some of these lands, commingled with other surface 
water, provided over 50 percent of the water used by fish and wildlife areas, and these waters 
still provide instream flows for fisheries and other beneficial uses. 

Several major dam, reservoir, and canal systems have been constructed and are operated in 
the Central Valley to serve agricultural and urban water needs. These projects have created 



57 



many severe problems for fisheries in the San Joaquin and other river systems. Although 
specific instream flow needs for many streams and associated fisheries in the valley have not 
yet been determined, it is apparent that instream flows in the mainstem San Joaquin (above 
its confluence with the Merced River) and in the major tributaries are currently inadequate to 
sustain migration of salmon. Further study is needed to determine instream flow needs of 
San Joaquin River fisheries. Additional planning, analysis, and field testing of methods to 
provide adequate and firm supplies of clean, fresh water for valley fish and wildlife are also 
warranted. 

Toxicity of Drainage-Water Contaminants 

Analyses of subsurface agricultural drainage water have revealed high salinity and elevated 
concentrations of toxic or potentially toxic elements (including arsenic, boron, cadmium, 
chromium, copper, lithium, manganese, molybdenum, nickel, selenium, strontium, uranium, 
vanadium, and zinc). Recent laboratory and field toxicity research reveals that fish and 
wildlife are more sensitive to the toxic properties of several of these chemical elements than 
previously believed. This is illustrated by the following examples for selenium, boron, and 
salts. 

The U.S. Environmental Protection Agency's ambient freshwater aquatic life water-quality 
criterion for selenium was recently reduced from 35 to 5 ppb. The State Water Resources 
Control Board and the Central Valley Regional Water Quality Control Board have 
recommended that water used for wetlands management in the Grasslands Subarea contain 
average selenium concentrations of 2 ppb or less. Furthermore, University of California 
scientists have identified 1.0 to 1.5 ppb waterborne selenium as the range that causes no 
adverse effects. Selenium concentrations in North Mud and Salt Sloughs in the Grasslands 
Subarea average 6.0 ppb. Selenium concentrations in the 7,000 acres of evaporation ponds 
average 49 ppb, based on acreage-weighted means, and range above 1,000 ppb. 

Boron, which was previously thought to be 
nontoxic to wildlife, has been shown to 
have adverse effects upon wildlife at 
concentrations of 900 ppm (dry weight) in 
the diet. Waterfowl food-chain organisms 
collected from Kesterson Reservoir and 
several other evaporation ponds in the 
valley have been found to contain 
concentrations of boron that approach or 
exceed this toxic threshold. 

Highly saline water, free from elevated 

concentrations of trace elements, can also 

pose a health threat to wildlife. For 

example, freshwater ducklings are very 

sensitive to salty water. Toxicity tests with 

mallard ducklings have shown that molt 

was slowed when they were provided a 

, f J • I • . » ■ ■ Embryo of a black-necked stilt deformed by 

smgle source of drmkmg water contammg selenium poisoning. 




58 



3,000 ppm total dissolved solids, and growth was reduced when their sole source of drinking 
water was 7,720 iJiS/cm electrical conductivity. In addition to containing elevated 
concentrations of various trace elements, evaporation ponds in the San Joaquin Valley, 
heavily used by ducks and other aquatic birds for nesting and rearing of young, are also very 
saline — up to 388,000 ppm TDS — and average 31,850 ppm TDS, about equal to seawater. 
The combination of saline ponds and the extremely limited acreage of freshwater wetlands in 
the southern San Joaquin Valley during the spring breeding season potentially increases this 
toxic threat to aquatic birds. 

Finally, the toxicity to fish and wildlife of various salts and trace elements carried in drainage 
water depends upon, among other variables, the species, life stage, health, and diet of the 
target organism; the chemical form of the contaminant; the bioavailability of the contaminant 
(which for waterborne concentrations can be affected by other chemical characteristics of the 
water); and the interactions (additive, synergistic, and antagonistic) of multiple contaminants. 
Very little information is available regarding many of these complex issues, and additional 
research is warranted. 

Contamination and Biological Effects 

Elevated concentrations of drainage-water contaminants have been discovered in water, 
sediments, food-chain organisms, and major vertebrates in a number of San Joaquin Valley 
areas outside Kesterson Reservoir and the San Luis Drain. These areas include rivers, 
streams, and ponds; riparian zones and wetlands; and upland sites. All these areas (both 
natural and manmade) provide fish and/or wildlife habitat. In several of them, elevated 
contaminant concentrations exceed documented toxicity thresholds, and studies have 
documented adverse biological effects that are believed to be contaminant-related. 

In the San Joaquin Basin, the same drainage water that previously was used to flood wetlands 
in the Grasslands area is now being discharged into various canals and natural channels for 
conveyance to the San Joaquin River. In the Tulare Basin, the number and size of 
evaporation ponds receiving drainage water have continued to increase. 

Evaporative concentration is dramatically increasing the waterborne concentrations of 
drainage-water contaminants such as boron and molybdenum in these ponds. In addition, 
through bioconcentration and possibly biomagnification, aquatic plants and animals can 
accumulate tissue concentrations of some drainage contaminants 100 to 10,000 times greater 
than those in the water. Statistically significant adverse biological effects (including impaired 
egg hatchability, elevated frequencies of embryo deformities, and reproductive failure) have 
been documented at seven of the valley's evaporation pond systems (about 58 percent of the 
ponds studied, which represent about 60 percent of the total acreage of ponds in the valley). 
Not all evaporation ponds have been studied, and efforts to date have focused upon breeding 
birds. Additional research is needed to determine whether adverse biological effects are 
occurring at other ponds and what effects, if any, operation of the ponds is having on 
wintering waterfowl and shorebirds, endangered species, and public health. Additional field 
research is also needed to field-test techniques for decontaminating and restoring 
drainage-water-contaminated fish and wildlife habitats and significantly reducing or 
eliminating the hazards posed to wildlife by evaporation ponds. 



59 




A test plot of eucalyptus trees (background) and atriplex (fore- and midground) being irrigated 
with drainage water. Plant transpiration reduces the water volume and concentrates the salts in 
the remaining drainage. 

Agroforestry Plantations 

Agroforestry plantations are being established in the study area in an attempt to reduce the 
magnitude of agricultural drainage-related problems. The trees (primarily eucalyptus) and 
halophytes (such as atriplex) are used to: (1) Lower the ground-water table and (2) reduce 
the volume of drainage water by increasing evapotranspiration. Recent studies have shown 
that the plantations provide habitat for several species of wildlife, including mourning doves, 
ring-necked pheasants, blacktailed jackrabbits, desert cottontails, a wide variety of songbirds, 
and possibly some large mammals such as foxes and coyotes. The plantations may benefit 
both farmers and wildlife. However, where they are irrigated with concentrated drainage 
water, more research is needed to determine whether these sites pose a contaminant hazard 
to wildlife. Appropriate management practices that will either increase wildlife values or 
reduce or eliminate contaminant hazards must be identified. 

PUBLIC HEALTH 

Public health concerns associated with drainage water were investigated during this study 
(Klasing and Pilch, 1988; Klasing, et al., 1990). Table 6 summarizes the concerns with 
drinking water, food crops, fish and game, and occupational exposures. 

Safety of Food Crops 

To date, selenium concentrations have been measured in about 125 food-crop samples grown 
in the western San Joaquin Valley, as well as in the milk and liver of some cows raised in the 
area. Overall, selenium concentrations in crops from the study area were similar to typical 



60 



U.S. selenium concentrations reported for those samples. Of the food samples analyzed, even 
daily consumption of the crops with the highest selenium levels found in the western part of 
the valley would not approach the quantity necessary for selenium toxicity. At most, they 
would provide part of the nutritional requirement for selenium in the human diet. The 
selenium content of cow's milk and liver obtained from the study area were similar to that for 
crops; however, the extent to which these cattle may have been exposed to elevated concen- 
trations of selenium is unknown. 

Certain crops in isolated areas may possibly contain higher concentrations of selenium than 
have been previously measured. If this is the case, persons who place heavy reliance on those 
foodstuffs to meet their dietary needs (such as may occur with subsistence gardening) would 
increase the risk of selenium toxicity. However, this has not been reported to have occurred 
in the westside San Joaquin Valley. Most consumers eat a variety of foodstuffs from many 
geographic areas. Persons whose consumption patterns are limited either to a small number 
of foodstuffs or to a very small geographic region may increase their risk of both deficiencies 
and excesses of trace elements in their diet. 

The risk to public health from potentially elevated concentrations of other agricultural 
drainage-water contaminants in foodstuffs is not known at this time. Currently, several other 
elements (arsenic, boron, and molybdenum) that have been found to be elevated in some 
agricultural drainage water are being analyzed in local food crops. 

Safety of Consuming Fish and Game 

Because selenium can be concentrated by some aquatic plants and invertebrates to levels far 
higher than those found in the water in which they grow, selenium from agricultural drainage 
water has become toxic to some aquatic birds that feed in drainage-contaminated aquatic 
environments. Fish and aquatic birds may in turn accumulate relatively high concentrations 
of selenium in their tissues, becoming a potential health risk to humans who consume them. 
A survey of these species at specific locations within the western San Joaquin Valley has 
shown that unrestricted consumption of contaminated fish or game over an extended period 
could cause recognizable signs of selenium toxicity. To date, however, selenium toxicity in 
humans has not been reported to public health officials or confirmed as a result of such 
consumption. 

Studies of other agricultural drainage-water contaminants in the tissues of fish and wildlife 
have not shown risks that exceed those from exposure to selenium. Therefore, procedures 
currently recommended to reduce selenium exposure from contaminated fish and wildlife (for 
example, health advisories to limit consumption of such game) can be expected to also 
protect the consumer from overexposure to other drainage contaminants. 



61 



Table 6. PUBLIC HEALTH CONCERNS ASSOCIATED WITH DRAINAGE WATER 



Constituent 



Drinking Water 



Food Crops 



Fish and Game 



Occupational 
Exposures 



Selenium 



Molybdenum 



Arsenic 



Some domestic wells in 
high-selenium areas may 
exceed the present EPA- 
recommended safe level of 
10 ppb. However, EPA has 
proposed raising the level 
to 45 ppb. See the Federal 
Register, May 22, 1989; 
vol. 54, no. 97. 

Daily consumption of wa- 
ter from some domestic 
wells in high-molybdenum 
areas may exceed recom- 
mended health levels. 

Some domestic wells in 
high-arsenic areas may ex- 
ceed recommended safe 
levels. 



Field tests suggest that 
normal consumption of 
crops is unlikely to exceed 
recommended dietary al- 
lowances. 



No standard defined. 



Regulatory standards are 
not developed. 



Consumption of fish and 
game from evaporation 
ponds and other contami- 
nated areas that exceed 
safe levels should be re- 
stricted. In most other 
cases, normal consump- 
tion would be unlikely to 
cause toxicity. 

No health-related data 
available. 



Consumption of fish and 
game from evaporation 
ponds and other contami- 
nated areas should be re- 
stricted. 



Workers should re- 
strict their exposure of 
direct contact with 
ele-vated levels of 
contaminants. 



Same as above. 



Same as above. 



Safety of Foraging 

Preliminary investigation of persons who forage in the western side of the San Joaquin Valley 
has not shown evidence of overexposure to selenium. However, substantial difficulties exist 
in obtaining and evaluating survey data of this nature. Thus, it cannot be assumed that the 
population of foragers in this region is safe from exposure to potentially toxic concentrations 
of agricultural drainage-water contaminants. Persons who make a regular practice of 
foraging would likely be at similar or greater risk from exposure to drainage contaminants 
than would fishermen and hunters, who are likely to eat a more varied diet. 

Occupational Exposures to Drainage Contaminants 

Concentrations of selenium in the blood and urine of personnel monitored during closure and 
cleanup operations at Kesterson Reservoir were within normal limits. Thus, it seems unlikely 
that such occupational exposures at sites similarly contaminated would cause above-normal 
selenium levels. Occupational exposures to other contaminants have not been evaluated. 
Because occupational activity may result in significant contaminant exposures by inhalation 
or dermal routes rather than by ingestion, different methods for assessing exposure and 
adverse health effects may be warranted. As an example, certain chemical forms of 
chromium and arsenic (and several other metals) are known to cause respiratory cancers or 
other chronic pulmonary diseases when inhaled. No investigation has been made of specific 
risks to workers from inhalation or dermal exposures to contaminants found at sites where 
drainage water has accumulated and concentrated (such as evaporation ponds or treatment 
facilities). No evidence is available to suggest that health risks from these exposure routes 
would be elevated for the general population. 



62 



Safety of Drinking Water 

Some ground-water sources of drinking water in westside San Joaquin Valley have 
concentrations of certain drainage constituents that can adversely affect human health, 
particularly when consumed over a long period. Arsenic, selenium, and nitrates have all been 
found in some domestic wells in the valley in concentrations that exceed current water-quality 
guidelines. With the exception of nitrates, these elevated concentrations are merely 
background levels that, in many cases, can be considered normal for these elements in the 
study area. Nonetheless, it is important to document when concentrations of substances 
exceed criteria set to protect an area's public health so that this information can be used in 
formulating drainage planning alternatives. 

SOCIAL CONDITIONS 

Community Infrastructure 

While the economies of the communities on the western side of the San Joaquin Valley are 
primarily based on agriculture, these towns have sufficient infrastructure and other 
commercial resources to adapt to broad changes in the valley economy. A number of these 
communities are currently experiencing significant growth caused by residential-development 
overflow from coastal metropolitan areas. The rural character of these towns is being rapidly 
altered as they become more suburban, with residents commuting to cities on the eastern side 
of the San Joaquin Valley, to the Santa Clara Valley, and to the San Francisco Bay area. The 
direct dependence of westside community residents on agriculture is diminishing because a 
larger proportion is working in nonagricultural jobs. 

The extent and rapidity of this suburbanization were not anticipated, and the emergence of 
zoning changes and subdivision development poses new problems for farms and wetlands in 
the surrounding areas. Given this continuing growth and high real estate prices in the 
metropolitan areas from which the newcomers originate, this transformation is expected to 
continue and even accelerate. 

Farm Labor 

Farm workers in the San Joaquin Valley are typically immigrants. Most come from Mexico, 
but significant numbers also come from Central America, Asia, and the Middle East. Only 
about ten percent of California's farm laborers were born and raised in the United States, 
and only about half of these are from California. Once they have arrived, a large minority of 
farm workers continues to migrate, either by moving back and forth between the U.S. and 
Mexico during the year or by following seasonal cropping patterns around the State. About 
37 percent of the State's farm workers take part in one of these forms of continuing migration 
(Mines and Martin, 1986). 

Crop specialization on valley farms has created seasonal employment for farm workers, who 
often secure a succession of short-term jobs to remain employed for most of the year. 
Although mechanization, new seeds, and improved production techniques are causing 
seasonality to decline, large numbers of seasonal farm workers are still employed in 
California (Martin, 1987). 



63 



r '~m Iff- - r n --^-- - — 



•.C) 





Large numbers of farm workers are needed to tend and fiarvest crops on the westside San Joaquin Valley. 

Farmers in the San Joaquin Valley depend more on hired labor than do farmers elsewhere in 
the U.S. Most farmers rely either on foremen to recruit laborers, usually without the direct 
involvement of top management, or on farm labor contractors, who hire farm workers and 
then contract with growers to provide a temporary workforce. The use of intermediaries to 
meet farm labor demands is becoming increasingly important in the State (Martin, 1987). 

Issues surrounding farm workers' health and safety are growing in importance as concern for 
public health and environmental quality focus attention on farm chemical use and other 
management practices. 

Water Supply and Drainage Management Organizations 

Most agricultural water management processes in the San Joaquin Valley either originate in 
organizations or are strongly mediated by them. At the most general level, valley water 
management is institutionalized within organizations and networks of interorganizational 
relationships that structure linkages among water users, local water management 
organizations, and government agencies. Responsibility for water-use policy, planning, and 
day-to-day activities affecting drainage-related agricultural water management in the valley is 
dispersed among a large number of public and private water management organizations. 
Public water management involves water agencies, joint power authorities, hundreds of 
special districts, county governments, and a plethora of State and Federal administrative and 
regulatory agencies. Private water management is structured by incorporated and 
unincorporated river water associations and nonprofit mutual water companies, numerous 
agricultural corporations, family farms, and other groups (Coontz, 1989 and 1990a). 

Water Management Networks 

No single organization or network shapes overall water management or is found in all phases 
of water management throughout the valley. Valley water management is shaped by a variety 



64 



of networks of private and public water management organizations. Network structures 
affecting agricultural water management at any given location and for specific kinds of water 
management activities are unique configurations of arrangements among various 
organizations. "Application" and "regulatory" networks are among the more important types 
affecting agricultural water management practices (Coontz, 1990b). 

Application networks develop programs to provide professional and/or financial assistance to 
both on-farm and local organization water managers with the aim of improving water 
management practices and facilities. University researchers, Federal and State agencies, and 
contract consulting firms are the cornerstones of application networks. 

Regulatory networks are composed of relationships among government regulatory agencies 
and various groups with interdependent interests tied to drainage management. Regulatory 
networks mediate conflicting interests by attempting to constrain and/or induce the 
discretionary activity of network participants so that they conform to a limited range of 
accepted actions and/or results. At least two qualitatively different regulatory networks, 
roughly corresponding to the valley's two hydrologic basins, shape regional regulatory 
strategies. These are a prescription-oriented network in the Tulare Lake Basin, which defines 
a range of acceptable actions to resolve drainage problems, and a performance-oriented 
network in the San Joaquin River Basin, which places more emphasis upon defining and 
meeting water-quality objectives. 

Regional Institutional Spheres 

In addition to organizations and networks, regional institutional spheres are important social 
structures that shape agricultural water management. They are configurations of unique 
political, economic, and social arrangements among and between water users and local water 
management organizations within a region. These spheres are more geographically restricted 
than regulatory networks and application networks. The principal institutional factors 
contributing to regionally specific variations that influence relationships among and between 
water managers within a region to outside organizations or government agencies include: 

(1) The degree to which formal or informal water management arrangements dominate, 

(2) the extent to which State or Federal agencies are integrated into water supply 
management, especially by the institutional structure of water rights and water contracts, 

(3) the degree to which agricultural water supply management and drainage management 
represent separate or integrated management structures, and (4) the relative importance of 
market relations in regional water management. The Drainage Program's five subareas 
roughly correspond to major regional institutional spheres (Coontz, 1990b). 

THE EXISTING INSTITUTIONAL STRUCTURE 

[Information in this section is summarized from a comprehensive study of water 
resources institutions sponsored by the Drainage Program (Thomas and 
Leighton-Schwartz, 1990). J 

Water management institutions and laws that can both contribute to and help solve drainage 
and drainage-related problems are best described by illustrating the "chain of custody" of the 
water that ultimately results in problem drainage. Governing all water use in the State is the 

65 



Constitution of the State of California. The Constitution provides that all water within the 
State is the property of the people of California. 

Though conceptually the physical resource remains a public asset, individuals may acquire an 
exclusive right to its use in the nature of a property right. But it is a highly qualified one. 
The State Water Resources Control Board oversees the allocation of these rights and the 
protection of water resources for the people of California. Private rights are conferred to 
those who exercise physical control over the water — be it surface or ground water — and 
put the water to a reasonable and beneficial use. Recognized beneficial uses pertinent to the 
drainage problem include irrigation, ground-water storage, and fish and wildlife uses. An 
"environmental water right" vests only where the water is diverted from its natural channel, 
as when it is applied to a refuge, but it does not vest when the water is left in the waterway. 

Specifically, appropriative and riparian water rights (post- 1914) are now administered 
through water permits issued by the State Board. Most of the irrigation water that eventually 
contributes to drainage is supplied through the Federal and State Water Projects as 
appropriative rights holders. However, appreciable amounts are supplied from ground-water 
pumping and local surface water. The Bureau of Reclamation holds water permits from the 
State Board entitling it to store, divert, and deliver water to the San Joaquin Valley through 
the Central Valley Project. The California Department of Water Resources holds permits for 
the water it develops and distributes to the valley through the State Water Project. 

In protecting the public's water resources, the State Board retains authority to modify these 
permits to prevent the unreasonable use of water. However, unlike the diversion of surface 
water, there is no State-administered permit system for ground-water extraction. 
Nonetheless, the State Board's authority to prevent waste and unreasonable use of water 
comes not only from its contractual rights under the permits it issues, but also from the State 
Constitution, which does extend to the use of ground water. This authority is codified in 
State law and provides that the State Board, on its own motion or by petition of DWR or an 
aggrieved person, may prevent the unreasonable use of any surface or ground water. 

In theory, this authority allows the State Board to require the Bureau of Reclamation and 
DWR, their contractors, or the end water user to take steps to reduce the generation of 
surface and subsurface drainage caused by excessive water application. In practice, however, 
the State Board has never used this power to address the drainage problem, and its exercise 
is sufficiently discretionary and judgmental that it is unlikely to provide a reliable solution to 
the overall problem. 

Moving down a link in the chain of water management and use, the Bureau of Reclamation 
and DWR provide water to local water entities, including water agencies, water districts, 
irrigation districts, mutual water companies, and joint-powers authorities through contracts. 
These irrigation water service contracts vary significantly, but generally impose repayment, 
place, and manner-of-use restrictions on the districts. Pursuant to Federal contracts, which 
are effective for 40 years and automatically renewable, water entitlement is a stated maximum 
volume of firm water supply in acre-feet per year and currently priced between $3.50 per 
acre-foot and $19.31 per acre-foot. The price depends on the cost of facilities that were 
necessary to develop and deliver the water at the time of the contract and annual operation 
and maintenance costs. When these contracts are renewed, water charges will be based on 



66 



annually adjusted cost-of-service rates. In 1990, Central Valley Project irrigation 
cost-of-service rates for the Delta-Mendota Canal and San Luis service areas varied between 
$13.58 and $23.01 per acre-foot (USER, 1989). Water use is restricted to agriculture, and may 
be neither transferred to another nor used outside the district's boundaries without the 
approval of the Bureau of Reclamation. 

Pursuant to State Contracts, which are effective for 75 years, the amount of total annual firm 
entitlement of State Water Project water that may be delivered in any month for agricultural 
use is limited to 18 percent of a contractor's annual entitlement amount. The price, which is 
based on the estimated actual operation, maintenance, energy, and capital recovery cost, is 
calculated annually. The 1990 price of State Water Project water in the San Joaquin Valley 
ranges from $32 per acre-foot to $67 per acre-foot (DWR, 1989). Transfers of SWP water 
must be approved by DWR. DWR seeks concurrence of all SWP contractors on transfers. 

The final link in the chain is the sale of the water from the district to the grower. Generally, 
growers have pro rata shares or entitlement to the district's water, and pay for it at a rate 
designed to defray the costs of capital facilities, contract charges from project operations, 
and administrative expense. A few districts are currently experimenting with tiered or 
progressive water rates that are designed to induce conservation of water in excess of 
minimal evapotranspiration and leaching requirements. Some also impose rules on the 
recycling of tailwater. Generally, however, growers are left unfettered with regard to their 
decisions on how much water to apply, when, and in what manner. Some districts, most 
notably Westlands Water District, do provide informational programs to their growers on 
these variables, expressly designed to help the growers minimize drainage generation. 

The regulatory institutions that govern the ultimate fate of drainage water in the valley's 
environment are predominantly State-created. The functions and dysfunctions of the 
regulatory system can be conveniently explained by referring to the public resources put at 
risk by drainage water. Existing regimes cover three of these resources: surface water, 
ground water, and wildlife. 

The State Board protects both surface- and ground-water quality in the State through 
water-quality standards developed by Regional Water Quality Control Boards. Water-quality 
standards consist of "beneficial-use" designations and "water-quality objectives" which are 
established to protect the beneficial uses. These are set as part of regional or statewide 
water-quality control plans in quasi-legislative proceedings. 

The Central Valley Regional Board has established a plan to protect San Joaquin basin 
surface water. The protection scheme, which is applicable to districts in the Northern and 
Grasslands subareas and the Westlands Water District, requires that drainers meet 
water-quality objectives for selenium, boron, and molybdenum. The Regional Board may 
revise the standards it established for selenium and boron because the Environmental 
Protection Agency, which has authority to oversee State water-quality protection, has 
determined that they do not protect beneficial uses. This scheme requires that drainers 
provide the Regional Board with plans, known as Drainage Operation Plans. The DOPs 
should include measures to reduce drainage and, hence, the amount of pollution discharged 
to the river. 



67 



Ground water is protected through State and Federal programs. Federal law provides little 
more than planning authority in protecting ground-water quality, but drives the protection of 
subsurface drinking water in California through standards established by the EPA. The 
primary focus of the Federal program is the prevention of contamination, rather than 
correction of existing pollution problems. 

The more comprehensive ground-water protection schemes are those imposed by the State. 
California's ground-water strategy is to maintain ground-water quality at a level that satisfies 
present and future drinking water needs and other beneficial uses (such as irrigation) and, 
where feasible, to restore ground-water quality to these levels. 

The State provides for two distinct kinds of ground-water protection standards: those 
relating to water quality and those relating to drinking water. Drinking-water standards 
address the quality of water at the point of delivery to consumers. Water-quality standards 
and drinking-water standards are established under two separate statutory schemes, 
administered by two different State agencies. The former is regulated by the State Board and 
the Regional Boards, and the latter is regulated by the California Department of Health 
Services. Additional protection is provided by the Department of Water Resources in its 
regulation of the design and construction of wells. 

Protection of both wildlife and ground water from drainage disposed of in evaporation ponds 
has come largely from the State. DHS and the Central Valley Regional Board are the 
agencies charged with regulatory responsibilities. DHS basically deferred regulation of valley 
ponds to the Regional Board, which issues permits for the pond operations. Ponds that 
contain drainage water that exceeds State hazardous waste threshold limits may be operated 
under an exception to the State's land disposal ban. This exception expires in 1992. 

The U.S. Fish and Wildlife Service is the principal Federal agency responsible for protecting 
and enhancing the nation's fish and wildlife resources, including preventing the unlawful take 
of migratory birds under the Migratory Bird Treaty Act. Its authority to protect migratory 
birds is broad. The agency may request Federal prosecution of evaporation pond owners and 
operators, which might lead to closure of ponds. To date, the USFWS has not prosecuted 
any San Joaquin Valley evaporation pond owners or operators. 

The California Department of Fish and Game has similar authority under State laws. Under 
the State Fish and Game Code, DFG may seek action by the Attorney General against the 
impairment of fish and wildlife, including drainage-related impairment such as contamination 
of surface-water habitats from drainage discharges. 

The fish and wildlife agencies may themselves be regulated by other Federal and State 
agencies. Specific to the drainage problem, USFWS and DFG are subject to the Regional 
Board's regulations for operations of their refuges and wildlife areas that discharge drainage 
water. The USFWS has prepared a Drainage Operations Plan for operation of the San Luis 
National Wildlife Refuge. 



68 



Chapter 4. THE PLANNING FRAMEWORK 



Planning takes place within an established framework of public sector policy and law and 
private sector resource use and management. This framework must be acknowledged in 
developing plans for solving drainage and related problems, and planning objectives and 
criteria must be based on it. 

This chapter outlines drainage-related public policy, local drainage management initiatives, 
and the planning objectives, methods, and criteria upon which plans presented in the 
following chapters are based. 

PUBLIC POLICY 

The policy base adopted for Drainage Program planning is discussed in the following sections 
in terms of drainage service, environmental protection, drainage studies and monitoring, and 
constraints. 

Drainage Service 

The need for management of drainage water has long been recognized by both the State and 
Federal governments and has been stated in a number of official documents, especially in the 
Federal legislation and administrative arrangements for supplying water to the western side 
of the San Joaquin Valley. Official recognition of the need for solving the drainage problem, 
if not indeed commitments for actually solving it, appears in legislative statements about 
"drainage service" or "drainage management plans." 

The legislation authorizing the San Luis Unit of the Federal Central Valley Project requires 
that an interceptor drain be provided for the Unit. Beginning in 1965 and each year since 
then, Congress has included a provision in the CVP appropriations act that prohibits 
selection of a final point of discharge for the San Luis Drain until certain conditions have 
been met. An appraisal-level study of the San Joaquin Valley Drain serving the entire valley 
was authorized in 1974 and completed in 1979 (IDP 1979), and a feasibility study was 
authorized in 1980 but was never completed. The funding of studies indicates the Federal 
government recognizes the need for a drainage solution. Construction of an 85-mile portion 
of the San Luis Drain demonstrates a Federal commitment to solve the problem. A 1986 
Federal court order in the compromise settlement of Westlands Water District v. United States 
of America requires the United States to develop and adopt a drainage plan acceptable to 
Westlands by December 31, 1991. 

The State of California has also acknowledged in a number of documents the need to manage 
agricultural drainage in the San Joaquin Valley. The California Water Plan (DWR, 1957) 

69 



recognized the need for drainage in areas proposed to be irrigated, especially on the western 
side of the San Joaquin Valley. The Tulare Basin has subsequently become a part of the 
area provided irrigation water from the State Water Project. In discussions with the Federal 
government regarding a master drain from the San Joaquin Valley, the State has, at various 
times since 1957, tentatively agreed to participate in such a drain, but has never actually done 
so. 

Environmental Protection 

Federal and State environmental protection laws, regulations, and local ordinances affect 
possible drainage-related strategies and provide objectives and constraints that must be 
satisfied in drainage plans. The primary laws relevant to drainage problems are: 



Federal 

Fish and Wildlife Coordination Act 
Migratory Bird Treaty Act 
National Environmental Policy Act 
Resource Conservation and 

Recovery Act 
Federal Endangered Species Act 
Clean Water Act 



State 

California Environmental Quality Act 
California Administrative Code: 

Title 22 (Hazardous Wastes) 

Title 14 (Natural Resources) 
California Fish and Game Code 
California Water Code 
Porter-Cologne Water Quality Control Act 
Toxic Pits Cleanup Act 
California Endangered Species Act 



For planning, it is assumed that, at a minimum, drainage plans will have to meet the 
objectives and standards embodied in or developed pursuant to these laws. The primary 
standards to be met from both State and Federal laws are included in the Level A 
performance standards presented in the "Planning Objectives" section of this chapter. 

Plans developed to comply only with present laws may not provide sufficient guidance for 
future decision-making. Efforts are under way to increase protection from additional 
potentially harmful substances introduced into the environment and to lower the permissible 
concentration of a toxicant or contaminant in the environment. Moreover, the trend of 
scientific discovery is toward revealing an increasingly complex natural environment. It is 
possible that even more stringent standards for environmental protection may apply in the 
future. To address a range of possible future conditions, plans will be developed for more 
stringent (Level B) performance standards. These standards are also presented in the 
"Planning Objectives" section of this chapter. 

The A and B levels of performance are presented to bracket a range of probable future 
conditions. Judgment must be exercised in limiting the enormous range of possible future 
conditions. For example, the Drainage Program has assumed that water-quality objectives 
will be set in terms of concentrations of substances allowable in receiving water, rather than 
in terms of the total load allowed in drainage water. This is a subjective assumption, not a 
declaration of a preference. 

Drainage Studies and Monitoring 

Intensive studies of causes and impacts of contaminant-related drainage problems began in 
1983 and were continued through the balance of the decade (see "Selected Bibliography" at 



70 



the back of this report). Ahhough much has been learned, knowledge of some aspects of 
drainage problems is still limited, and many uncertainties about solving the problems remain. 
Areas of limited knowledge include interactive and long-term effects of contaminants on fish 
and wildlife, levels of public health risk posed by contaminants, specific causes of water table 
rise and deterioration of water quality on small land units, the long-term sustainability of 
agriculture under existing hydrologic and economic conditions in the valley, and future 
drainage conditions. To learn more, the effects of the drainage problem on the environment 
should be monitored. 

The basic strategy of monitoring should be to identify and collect information on biota, soils, 
and the water regime so that changes in drainage problems and conditions can be 
determined, particularly in response to actions taken to solve the problem. Plans can then be 
re-evaluated periodically and adjusted in light of new knowledge and new conditions. Design, 
funding, and implementation of a comprehensive long-term monitoring program are needed. 

Constraints 

In addition to the laws and performance standards cited previously, two Drainage Program 
policies further constrain planning. All alternative plans must: (1) Meet the water-quality 
objectives of the State of California, and (2) focus on in-valley solutions. [Action by the 
Drainage Program Policy and Management Committee on June 15, 1987.] 

Objectives for both surface- and ground-water quality adopted by the Central Valley Regional 
Water Quality Control Board and approved by the State Water Resources Control Board 
have become objectives for plan development. Level B performance standards make 
provision for more stringent standards in the future. 

The focus on in-valley solutions precluded study by the Program of the removal of drainage 
water from the valley by any means other than the San Joaquin River. This policy did 
recognize, however, the need to study and describe the distribution and fate of salts in the 
drainage problem area. 

LOCAL DRAINAGE MANAGEMENT INITIATIVES 

Initiatives by local water management organizations to manage drainage and related 
problems are presently under way in each subarea, and it appears they will contribute to 
improving management of the problem. Most local initiatives to improve existing water 
supply and drainage management practices involve outside cooperators, sponsors, regulators, 
or other participants. These efforts are typically implemented through a variety of 
organizational and institutional arrangements that link individual water users, local and 
regional water management organizations, university researchers, and State and Federal 
agencies (Coontz, 1990b). Local initiatives should be encouraged, supported, and 
coordinated as part of an overall management plan. 

Many local initiatives are not mentioned in the alternatives and recommended plan presented in 
the following chapters because the plan is not detailed. Some of the more significant of these 
include: (1) on-farm water management evaluation and conservation programs; (2) drainage 



71 



reuse, treatment, and disposal studies and demonstration projects; and (3) construction of new 
water management facilities and improvements to existing facilities. Local initiatives seeking to 
reduce drainage volumes, effect institutional change, restore and protect fish and wildlife 
habitat, and develop workable methods of treating and disposing of drainage water are 
important contributors to management of the problem and are considered part of the plan. 

PLANNING OBJECTIVES 

The technical objectives that guided formulation of alternative plans are stated in terms of 
specific aspects of drainage and drainage-related problems: water quantity, water quality, 
land use, and public health. 



• 



Water quantity objectives pertain to control of ground-water levels by managing the 
water in and out of the shallow aquifer and to provision of fish and wildlife water 
supplies. 

• Water quality objectives involve allowable water constituent levels of the San Joaquin 
River, Salt and Mud Sloughs, ground water pumped to lower water tables, evaporation 
pond influent, and wetland and agricultural water supplies. 

• Land use objectives stress future maintenance of agricultural productivity. 

• Public health objectives are concerned with protecting the public from the possibility of 
contaminated fish, wildlife, and agricultural foodstuffs. 

Table 7 lists the planning objectives and quantifies them, where applicable. Performance 
Levels A and B are shown for each objective, even when they are the same. The need for and 
use of performance levels were described previously in the section of this chapter on 
"Environmental Protection." 

PROGRAM PLANNING METHODS 

The method used to formulate and evaluate alternative plans is described in the Drainage 
Program's report. Formulating and Evaluating Drainage Management Plans for the San Joaquin 
Valley (1988). [Details of the planning procedures and their application are presented in a 
Drainage Program technical report (D.G. Swain, 1990).] Early in this Program, over a 
hundred ideas and concepts for solving part or all of the drainage problem were screened 
and reduced to some 80 drainage and drainage-related management options. These options 
were further evaluated through an extensive review period for technical feasibility, potential 
effectiveness in solving the drainage problem, cost, and acceptability to the public. This 
reduced the number to about a dozen major options that could be combined in various ways 
to manage or solve drainage problems on the western side of the valley. 

For each subarea, those options effective in reducing the drainage-water problem were 
combined into three planning alternatives that emphasize: (1) Source Control (the 
conservation and reuse of agricultural water), (2) Ground-Water Management (the extraction 



72 



Table 7. PLANNING OBJECTIVES, CRITERIA, AND STANDARDS 



ITEM 



OBJECTIVE 



Performance 
Level A 



Performance 
Level B 



Plan/design average regional deep percolation 
that must be managed after 0.02-0.35 ac-ft/acre/yr 
reduction by source control measures 

Plan/design minimum depth to water table 

Criteria for conditions required for deep 
pumping of semiconfined aquifer 

Water supply to fish and wildlife 



WATER QUANTITY 

0.4 ac-ft/ac/yr 



5 feet 

Minimum combined 

aquifer thickness 

of 100 feet 



0.4 ac-ft/ac/yr 



5 feet 

Minimum combined 

aquifer thickness 

of 200 feet 



a. Water conserved by reducing deep percolation could 
be used to meet drainage water replacement water 
needs and alternative habitat water requirements asso- 
ciated with evaporation ponds. Water for restoration of 
drainage-contaminated wetlands will also be included. 

b. Additional water supplies needed to improve fish and 
wildlife resources will be quantified, and possible 
sources and means of supply will be identified. 



WATER QUALITY 
(Mean monthly values, unless otherwise noted) 

San Joaquin River (Mouth of Merced River to Vemalis) 

Total Dissolved Solids, near Newman (ppm) 
Total Dissolved Solids, near Vemalis (ppm) 

Boron, near Newman (ppm) 



Selenium, near Newman (ppb) 

Molybdenum, near Newman (ppb) 

Salt and Mud Sloughs and San Joaquin River, Sack Dam to Mouth of Merced River 

TDS (ppm) 
Boron 4>pm) 
Selenium (ppb) 
Molybdenum (ppb) 

Pumped Ground-Water Aquifer Limits 

TDS (ppm) 
Boron (ppm) 
Selenium (ppb) 

a Objectives not presently established or estimated. 

b Slate Water Resources Control Board staff recommendations In "Regulation of Agricultural Drainage to the San Joaquin River," 
August 1987. USEPA has disapproved certain of the Board's objectives and the matter is presently unresolved. 

c U.S. Bureau of Reclamation and Souih Delta Water Agency agreement. 

d Central Valley Regional Water Quality Control Board Resolution No. 88-195, Adoption of Amendments to the Water-Quality 
Control Plan for the San Joaquin River Basin (5C). 

e Grassland Water District agreement with agricultural drainers. 



a 

450' 


650" 
450' 


0.8" 
(3/15 - 9/15) 

1.0" 
(9/16 - 3/14) 

1.3" 
(Critical year only) 


0.7" 


5" 


2* 


8" 
(Critical year only) 

10" 


10" 


uth of Merced River 




a 

2" 
10" 
19" 


2,000" 

2" 

2 

10" 


1,250 
1.0 
5.0 


1,250 
0.5 
2.0 



73 



Table 7. PLANNING OBJECTIVES, CRITERIA, AND STANDARDS (continued) 



ITEM 



OBJECTIVE 



Performance 
Level A 



Performance 
Level B 



WATER QUALITY (continued) 



Evaporation Pond Influent (concentrations that may eliminate 
the need for hazing and alternative habitat) 

Selenium (ppb) 
Molybdenum (ppb) 
Arsenic (ppb) 

Wetland Water Supply (average monthly concentration) 

TDS (ppm) 
Boron (ppm) 
Selenium (ppb) 
Molybdenum 
Arsenic 

Agricultural Water Supply (average monthly concentration) ' 
TDS (ppm) 

Boron (ppm) 



Agricultural use 



2,500' 
2 



1,250 
1 
2 



500 « 


1,250 « 


2.500 " 


2,500" 


0.5* 


1.0 « 


2.0' 


4.0' 


LAND USE 




Maintain existing irrigable 


Maintain irrigated agri- 


lands in production, except 


culture on lands over- 


for land needed for drain- 


lying exceptionally high 


age water reuse (trees), 


concentrations of selenium 


disposal activities, and 


in ground water, if econo- 


urbanization. 


mically feasible; if not 




feasible, retire the land. 



PUBLIC HEALTH 



Fish 

Selenium objective for San Joaquin River (ppb) 

Wildlife 

Selenium objective for evaporation ponds (ppb) 

Agricultural Foodstuffi 



5' 

Use irrigation water (both 
surface & ground water) & 
soil that will not produce a 
health risk in agricultural 
crops, animals, or animal 
byproducts. 



1.0-1.5 " 

Use irrigation water (both 
surface & ground water) & 
soil that will not produce a 
health risk in agricultural 
crops, animals, or animal 
byproducts. 



f Level B criteria for agricultural water supply show the effect of increased (compared to Level A) water conservation on farmland 
and increased restrictions on drainage discharge; that is, more salt and boron would be excluded from receiving water through reuse 
and recirculation of drainage water. 

g This objective is based on crop yield vs. irrigation efficiency and uniformity analysis for beans (a salt/boron-sensitive crop) and 
cotton (a sall-Iolerant crop). 

h Wafer-quality limit for direct use of water (without blending) for irrigation of salt-tolerant crops, using management strategies pro- 
posed (Rhodes. 1987). 

i Diluted subsurface drainage used for irrigation of cotton and other boron-tolerant agricultural crops. 

j Ambient fresh-water aquatic life criterion (USEPA, 1987). May require warnings for consumption of fish and wildlife by pregnant 
women and young children. 

k "No adverse effects level" (UCCC, 1988); "no adverse effects level" (Davis el al., 1988). 



74 



of irrigable water from deep within the semiconfined aquifer to lower the near-surface water 
table in waterlogged land areas), and (3) Land Retirement (the retirement of irrigated 
agricultural lands overlying shallow ground water that contains greatly elevated 
concentrations of dissolved selenium and that are difficult to drain). Planning alternatives 
were devised for both Level A and Level B performance standards. 

Comparison of the alternatives permitted drawing conclusions that were useful in formulating 
the recommended plan. The plan is the optimum mix of the planning alternatives used to 
reduce the drainage-water problem, coupled with fish and wildlife resource components. 

ESTIMATING THE VOLUME OF WATER 
CAUSING DRAINAGE PROBLEMS 

The term problem water was coined by the Drainage Program to represent the volume of 
subsurface water that occurs (or will occur) in a given place to cause a drainage problem. A 
drainage problem exists when there is a condition of too much shallow ground water 
occurring in the root zone of crops — associated often with concentrations of dissolved salt 
or boron in that water that reduce crop production and/or increase farm management costs. 
A grower experiencing economic loss under this condition has three choices: (1) Grow more 
salt-tolerant or boron-tolerant plants (at less profit), (2) abandon irrigated agriculture on this 
land, or (3) apply drainage management to this land. Such management usually begins with 
installing artificial drains to remove the subsurface drainage volume. If potential toxicants 
such as selenium are present in the drained water, storage or disposal becomes more 
difficult, costly, and potentially hazardous to the environment. 

Problem water is generally ground water that is less than 5 feet from the surface of the land. 
In a hydrologic sense, considerably deeper water can move along a pressure gradient and up 
from greater depths into the 0- to 5-foot zone (Belitz, 1988); thus, as long as the regional 
water table remains high, other ground water is continually replenishing the problem water. 
The irrigated area that is, and likely will be, affected by a 0- to 5-foot water table is shown in 
Table 8. The forecasts are based on observed trends between 1977 and 1987, modified by 
physical limitations of the total area that will develop high water table conditions. These 
lands are considered to have a potential drainage problem. They are considered to have an 
actual drainage problem if and when the quality of water in the root zone causes one of the 
grower reactions indicated previously. Tlie estimated extent of the drainage problem area 
(underlain by problem water) is shown in Table 9. The drainage problem area is smaller than 
the area with a water table less than 5 feet from the ground surface because of water-quality 
conditions. 

The shallow ground-water area (0 to 20 feet from the land surface) was divided into 
water-quality zones to aid in determining drainage problem areas and to aid in planning. 
The divisions, which were made on the basis of the concentration of salts and trace elements 
in the shallow ground water, are shown on Figure 18. Problem water occurs in these zones 
and, by 2040, will affect most of the land within the zones. 

The annual volume of problem water targeted for management is the average annual amount 
of water added each year to the root zone (largely through irrigation) in excess of water that 



75 



percolates to deep aquifers. This problem water is water that remains in the root zone area, 
redissolving salts and other substances, evaporating up through the soil column, and 
becoming loaded with increasing concentrations of minerals as the summer irrigation season 
advances. Table 10 provides an estimate of the annual volume of problem water in each 
subarea for 2000 and 2040. For the whole study area, the unit volume of problem water 
in 2000 is forecasted as about 0.70 acre-foot per acre of problem area; and for 2040. it is 
forecasted as about 0.75 acre-foot per acre. The increase is due to the slow but steady trend 
toward increased mineralization that will occur in some subareas before a coordinated effort 
to manage the drainage problem can get under way at the scale required. 



Table 8. FORECAST OF IRRIGATED AREA WITH WATER TABLE 

LESS THAN 5 FEET FROM GROUND SURFACE 

(Based on Existing Trends) 

In 1,000s of acres 



Subarea 


1990 


2000 


204( 


Northern 


49 


49 


49 


Grasslands' 


230 


230 


230 


Westlands 


104 


170 


227 


Tulare 


320 


359 


387 


Kern 


62 


110 


164 



TOTAL 



765 



918 



1,057 



' Excludes 90,000 acres of wetland habitat with a high water table. 

Note: All currently drained lands are included, even though drainage may have lowered 
the water table below 5 feet. 



Table 9. FORECASTS OF EXTENT OF DRAINAGE PROBLEM AREA 

In 1 ,000s of acres 



Subarea 

Northern 

Grasslands 

Westlands 

Tulare 

Kern 



2000 

34 
116 
108 
125 

61 



2040 

44 
207 
204 
348 
148 



TOTAL 



444 



951 



Note: Total area in 2000 revised upward from 409,000 acres in SJVDP's Preliminary Planning 
Alternatives. August 1989. 



76 



Table 10. ESTIMATE OF ANNUAL PROBLEM WATER VOLUME 
In 1,000s of acre-feet 



2000 



2040 



Northern 

Grasslands 

Westlands 

Tulare 

Kern 



26 
86 
81 
75 
46 



38 
155 
153 
209 
HI 



TOTAL 



314 



666 







0' 



•i 



Sffii^^Jlg^^ 



'^^^S^iH&iSif 




'Pmfy 



r' **■■ ■ ' ' 9*3- - 







In most areas where the ground-water table is less than 5 feet from the 
land surface, water is drawn upward and evaporates, leaving a deposit 
of salts on the surface and in the root zone that retards or prevents the 
growth of many crops. 



77 



Figure 18 

SHALLOW GROUND-WATER QUALITY ZONES 




I i\\ii iiii' 



UGENd 

Edge of Valley Floor 
General Study Area Boundary 
Subarea Boundary 

Shallow Ground Water Quality Zone 



78 



SJVDP 



Chapter 5. IN-VALLEY MANAGEMENT OPTIONS 
AND PLANNING ALTERNATIVES 



This chapter reports the results of analyses made by use of the planning process described in 
Chapter 4. The analyses are a necessary transition step toward laying out a recommended plan. 

First, an estimate is presented of the future drainage problem and its consequences, assuming 
present trends continue and no coordinated and comprehensive action is taken by local. State, 
and Federal entities to solve drainage problems. This is called the Future- Without Alternative, 
and it is useful as a basis for comparison with planned actions for the future. Next, planning 
building blocks, called "options," are described. These can be fitted together in compatible mixes 
to form alternatives to the future-without alternative. Finally, three planning alternatives that 
emphasize different strategies are formulated and displayed as a basis for designing the 
recommended plan presented in Chapter 6. 

THE FUTURE-WITHOUT ALTERNATIVE 

The future-without alternative represents conditions that could develop in the valley if 
coordinated, comprehensive actions are not taken by local, State, and Federal entities to solve 
drainage and drainage-related problems. The President's Council on Environmental Quality 
requires that all Federal planning studies include a future-without alternative as part of project 
planning. The future-without alternative is intended to give planners and the public a common 
ground from which to judge the need for actions to change present trends. It is also a baseline 
against which the economic, environmental, social, institutional, and physical effects of planned 
actions may be measured to determine their positive or negative effects. 

Development of the future-without alternative involves: (1) Describing a general, overall theme for 
the future in the valley; (2) developing a set of assumptions about economic, environmental, social, 
institutional, and physical conditions in the valley and projecting trends; and (3) quantifying the 
effect of these assumptions on the planning subareas. 

The Overall Theme 

In February and March 1987, the San Joaquin Valley Drainage Program conducted multi- 
disciplinary workshops designed to develop future scenarios of conditions that would likely prevail 
in the absence of a coordinated, comprehensive plan to solve the valley's drainage and 
drainage-related problems. Participants included valley farmers, wildlife refuge managers, water 
district managers, academicians and researchers, and Federal and State agency personnel. The 



79 



groups discussed major themes and trends that were forcing changes in agricultural 
drainage-related conditions in the valley. They concluded that central themes shaping future 
trends were related primarily to the public's desire to protect fish and wildlife and to sustain 
agriculture in the valley (SJVDP, 1987). 

Assumptions About the Future 

Assumptions regarding future economic, environmental, social, institutional, and physical 
conditions and trends in the valley are summarized below. Two overriding assumptions are that 
no catastrophic natural events and no major changes in the national political, economic, or social 
climate would occur. 

More specific assumptions and trends are: 

• The present trend toward less Federal government participation and more 
privatization would continue. Government expenditures for major water projects 
would continue to decline, and Federal farm subsidies would be reduced gradually. 
More responsibility for natural resources management would fall on State and local 
governments and the private sector. 

• Public pressure for environmental protection would increase, leading to more stringent 
environmental regulations, and increased governmental enforcement of those 
regulations. This could result in user charges, taxes, and penalties to aid 
environmental protection. 

• Agricultural economic conditions would remain relatively stable. The United States, 
the State of California, and the San Joaquin Valley would compete favorably in world 
agricultural markets. Irrigated agriculture in the valley would be able to afford and 
install some drainage improvements but would not be able to do so uniformly, and 
some land would be removed from production as a result of drainage and related 
problems. 

• California's population would continue to grow, increasing the urbanization of the San 
Joaquin Valley, including westside agricultural lands, more of which would be 
converted to urban, residential, commercial, and industrial uses (with their attendant 
transportation and communication needs). Air pollution, waste generation, and noise 
would increase. 

• Importation of water to the study area would not be significantly increased. 

• There would be a shift in the northern part of the valley from agricultural water use to 
urban uses. 

• Existing public wildlife areas would be preserved and protected, but no new areas or 
water supplies would be developed. Wetlands acreage on both public and private 
wildlife areas would diminish as their intermittent water supplies disappeared. 

• Overall, surface- and ground-water quality in the study area would continue to 
deteriorate. 

• Tlie land area adversely affected by a high ground-water table would increase. The 
shallow ground water would become more saline, and, as a result, agricultural land 
would be removed from production. 



80 



• Except for use of the San Joaquin River, in conformance with water-quality objectives, 
no drainage outlet from the valley would be provided. 

• The rate of adoption of water conservation measures in drainage problem areas would 
increase. 

• Independent and uncoordinated actions related to agricultural drainage would result 
in litigation, not only between agricultural and environmental interests but also among 
groups having similar interests. 

• Piecemeal legislation and institutional change would add to the drainage problem, 
causing the range of choices for water, land, and fish and wildlife managers to narrow 
and bringing significantly higher costs to most concerned parties. 

The Shape of the Future Under the Future-Without Alternative 

The future-without alternative, as shaped by assumptions described in the previous section, is 
described here in terms of land-use change and assessments of the hydrologic, economic, fish and 
wildlife, public health, and social effects of that change. 

Land-Use Change 

Analysis of present trends toward change in the future hydrologic system of the western side 
provided estimates of irrigated land, land abandoned due to salinization, and land drained by 
2000 and 2040 (Table 11). The main conclusion drawn from these estimates and from backup 
data compiled in the Drainage Program's technical reports is that the absence of a clear, 
comprehensive approach to drainage management would likely lead to soil salinization and the 
abandonment of about 460,000 acres of irrigated agricultural land by 2040. The result would be 
major losses in agricultural production. 

Table 11. IRRIGATED LAND CHANGES UNDER THE FUTURE-WITHOUT ALTERNATIVE 

In 1,000s of acres 





1990 


2000 


2040 


SUBAREA 


Drained 
Area 


Irrig- 
able 
Area 


Irri- 
gated 
Area' 


Drained 
Area 


Aban- 
doned 
Lands^ 


Change 
to Urban 

Land 

Use 


Irri- 
gated 
Area' 


Drained 
Area 


Aban- 
doned 
Lands' 


Change 
to Urban 

Land 

Use 


Irri- 
gated 
Area' 


Northern 


24 


165 


157 


34 





5 


152 


51 





25 


133 


Grasslands 


51 


365 


329 


85 





4 


325 


152 


40 


20 


225 


Westlands 


5 


640 


576 


50 


28 





551 


49 


140 


5 


446 


Tulare 


42 


612 


551 


86 


38 





517 


94 


190 


5 


325 


Kern 


11 


762 


686 


14 


18 


5 


665 


40 


90 


35 


573 


TOTAL 


133 


2,544 


2,299 


269 


84 


14 


2,210 


386 


460 


90 


1,802 



Irrigated area is 95% of the irrigable area in the Northern Subarea and 90% of all other subareas. 

Calculated as 20 % of the 2040 abandoned land estimate, except Grasslands, where discharge to the river is expected 

to forestall salinization and resultant abandonment until after 2000. 

Irrigated area is 90% of the difference between the irrigable area and the sum of the land abandoned and land changed to 

urban, except in the Northern Subarea where the factor is 95%. 

Values based on WADE model analysis, using estimated 2040 area with water table less than 5 feet from ground surface, and 

present salinity and selenium concentrations in shallow ground water (0 to 20-foot depth). 



81 



By 2040, salinization of irrigated land could be expected to diminish the irrigated area by about 
11 percent in the Grasslands Subarea, 22 percent in the Westlands Subarea, 31 percent in the 
Tulare Subarea, and 12 percent in the Kern Subarea. No irrigated land in the Northern Subarea 
would be affected. 

Hydrologic Effects 

A general reduction in irrigated agricultural water requirements is expected in areas with shallow 
ground water at or near 5 feet in depth. This could occur because of increasing contributions of a 
very high water table to evapotranspiration and abandonment of waterlogged lands. The shallow 
ground water would become more saline, as would overlying lands. On affected lands, this 
condition would change farming practices and selection of crops grown. Eventually, the value of 
the lands for irrigated agriculture would decline to a level that would force abandonment of the 
lands. Changes in land use within the study area, including conversion of irrigated lands to 
residential and commercial development, would also reduce irrigation deliveries. 

Limited opportunities to dispose of drainage would gradually reduce water deliveries to the lands 
with rising soil salinity during the next 50 years. Estimated reductions of irrigable land areas and 
irrigation water requirements due to salinization, changes in land use, and a modest increase in 
irrigation application efficiencies are shown in Table 12. 

The quality of water provided by the State and Federal water projects would not change 
significantly throughout the planning horizon. However, the water in crop root zones would 
become more saline and, in places, would become loaded with boron due to increased evaporation 
of water from a near-surface water table. 

The present quantity of firm water supply available for wildlife management areas would probably 
diminish under the future-without alternative. In a normal year, firm water deliveries of 
97,000 and 17,000 acre-feet are available, respectively, to wetlands within the Grasslands and 
Northern subareas. These amounts do not allow for any replacement of the selenium- 
contaminated drainage water used for wetland management. 

Table 13 shows that the quantity of subsurface drainage would be expected to more than double 
the present level by 2040. These estimates reflect the effects of increasing on-farm source control 
measures to reduce deep percolation by an average of 0.20 acre-foot per acre in the Grasslands, 
Westlands, and Kern subareas and 0.05 acre-foot per acre in the Tulare Subarea. The estimate 
reflects no reduction in the Northern Subarea. In contrast, the average target adopted for the 
Drainage Program's planning alternatives is 0.35 acre-foot per acre in the Grasslands, Westlands, 
and Kern subareas, and 0.20 acre-foot per acre in the Tulare Subarea, with no reduction in the 
Northern Subarea. 



82 



Table 12. CHANGE IN IRRIGABLE AREA AND WATER REQUIREMENT 
UNDER THE FUTURE-WITHOUT ALTERNATIVE 





Irrigable Area^ 
(1 ,000s of acres) 


Total Irrigation Water Requirement^ 
(1 ,000s of acre-feet) 


Subarea 


Present 


2000 


2040 


Present 


2000 




2040 


Northern 

Grasslands 

Westlands 

Tulare 

Kern 

TOTAL 


165 
365 
640 
612 
762 

2,544 


160 
361 
612 

574 
739 

2,446 


140 
305 
495 
417 
637 

1,994 


530 
1,180 
1,580 
1,300 
2,040 

6,630 


520 
1,140 
1.470 
1,220 
1,870 

6,220 




460 
9-/0 

1,190 
880 

1,610 

5,110 



In any given year, about 90% of this area is actually being irrigated, except for the Northern 

Subarea, where 95% is irrigated.. 

The procedure used to estimate the water requirement is described in D.G. Swain (1990). 



Table 13. ESTIMATED SUBSURFACE DRAINAGE VOLUME 

UNDER THE FUTURE-WITHOUT ALTERNATIVE 

In 1 ,000s Of acre-feet 



Subarea 



Present 



2000 



2040 



Northern 

Grasslands 

Westlands 

Tulare 

Kem 



TOTAL 



18 
38 

4 
32 

8 

100 



26 
54 
28 
47 
8 

163 



37 
105 
27 
52 
22 

243 



The present weighted average concentration of salts in drainage water estimated to occur in each 
of the water quality zones varies from about 1,000 to 25,000 parts per million total dissolved 
solids. Under future-without conditions, the quality of the shallow ground water would improve 
gradually in areas of high salinity where drainage is provided and salts are leached from soils. 
However, in undrained areas with a high water table, the lands may have become salinized before 
the quality of shallow ground-water had improved significantly. 

Economic Effects 

The future-without conditions were analyzed for 2040, and the agriculturally related economic 
impacts are compared to present conditions in Table 14. Overall, the future-without would exhibit 
a net decline in irrigated acreage, income, sales, and jobs. About 554.000 acres would be 
abandoned or converted to noncrop uses, with an associated loss of crop value of about 
$440 million per year. The negative impacts on retail sales in the surrounding communities would 
be about $63 million annually. Personal income in the study area would be reduced by over 
$123 million annually. 



83 



Table 14. REDUCTION IN RETAIL SALES, INCOME, AND EMPLOYMENT FROM 
PRESENT TO FUTURE-WITHOUT CONDITIONS, 1987-2040 





Subarea 




Item 


Grasslands 


Westlands 


Tulare 


Kern 


Total 


Reduction in irrigated crop 
area (1,000s of acres) 


62 


151 


210 


131 


554 


Lost crop value 


42,747 


130,344 


175,452 


92,712 


441,255 


Direct retail sales 


1,555 


4,743 


6,385 


3,374 


16,057 


Indirect and induced retail sales 


4,545 


13,903 


18,804 


9.913 


47,165 


Total retail sales 


6,100 


18,646 


25,189 


13,287 


63,222 


Direct personal income 


5,362 


16,532 


22,637 


11,859 


56.390 


Indirect and induced 
personal income 


7,285 


29,805 


14,376 


15,441 


66,907 


Total Income 


12,647 


46,337 


37,013 


27,300 


123,297 


Direct employment 


399 


1,183 


1,519 


822 


3,923 


Indirect and induced 
employment 


1,020 


2,160 


1,022 


1,071 


5,273 


Total employment 


1,419 


3,343 


2,541 


1,893 


9,196 



Note: Crop value, retail sales, and income are in 1,000 (1990) dollars per year and employment is in person-years per year. 



Employment projections indicate that total agricultural employment in the four subareas would 
fall by nearly 4,000 jobs. The loss of agricultural production would cause more than 5,000 jobs to 
be lost in the supporting industries and communities serving agriculture. Overall employment 
losses could reach nearly 9,200 jobs. 

The secondary and induced impacts would be felt statewide, with the greatest experienced in the 
valley communities and the balance predominantly felt in the San Francisco Bay area and the Los 
Angeles basin. 

This analysis does not take into account the value of resources freed after lands are abandoned. 
Depending on the assumptions concerning the reallocation of water and the fate of the lands 
abandoned, other positive values could be expected. Alternative uses for the abandoned or 
reallocated resources could be expected to exhibit some compensating income and employment 
characteristics. 

The loss of fish and wildlife habitat and populations in the San Joaquin Valley associated with 
future-without conditions would mean less direct recreational use of these resources. This would 
result in regional economic impacts in the form of reduced retail sales, personal income, and 
employment. In addition, the value society receives from simply knowing that environmental 
resources in the valley exist and that the option exists to use these resources would be reduced 
under future-without conditions. No estimates have been made of the economic values and 
regional economic impacts for future-without conditions, compared to present conditions. 



84 



Other agricultural areas that produce similar crops could benefit when competitors abandon their 
lands. The net result of such a regional shift has not been analyzed. However, it is expected that 
the bulk of net acreage and crop reductions would occur in relatively salt-tolerant row and grain 
crops, such as cotton and wheat. 

Clearly, a major reallocation of resources would occur. Water, land, and labor would be only part 
of the picture. The losses to the financial community and the local tax base would be substantial. 
Losses in land asset value could encourage a new round of investment at a lower cost. However, a 
net outmigration of investment capital would probably occur in heavily impacted valley 
communities. 

Effects on Fish and Wildlife Resources 

Without a firm supply of suitable quality water delivered when needed, the total acreage of 
healthy wetlands in the valley would continue to decline. At present, there are about 85,000 to 
90.000 acres of seasonal and permanent wetlands in the valley. It is estimated that, by 2040, only 
about 55,000 acres (those with firm water supplies) would remain. Populations of migratory and 
resident wildlife species dependent on those scarce habitats would decline. Effects on 
populations of wintering migratory birds (waterfowl, shorebirds, and long-legged wading birds, for 
example) would probably be especially severe as birds crowded into ever-smaller areas of habitat, 
increasing the incidence and impact of avian diseases. Opportunities for such human uses of 
these wildlife resources as bird watching, nature study, and waterfowl hunting would diminish or 
even be prohibited. 

Even with hazing and other similar efforts, evaporation ponds containing elevated concentrations 
of selenium, boron, arsenic, molybdenum, uranium, other trace elements, and salts would 
constitute an extremely serious contaminant hazard to wintering and resident populations of 
aquatic birds. Operation of toxic ponds could also pose contaminant hazards to endangered 
predators known to occur in the southern end of the valley (for example, the bald eagle. American 
peregrine falcon, and San Joaquin kit fox). The development and operation of expanded or new 
pond acreage would likely impact populations of several other endangered species. Because 
elevated concentrations of selenium were found in tissues of birds taken from some evaporation 
ponds, a public health warning was issued, advising hunters to limit or discontinue their 
consumption of waterbirds taken from those ponds. All these contaminant hazards would be 
compounded by the decreasing acreage of clean wetlands habitat. 

Agroforestry plantations, developed to aid drainage management, would provide valuable new 
habitat for a variety of birds, mammals, and other species of wildlife, if the tree farms do not pose 
a contaminant hazard. 

Water-quality objectives for the San Joaquin River basin adopted by the Central Valley Regional 
Water Quality Control Board still allow certain waterways to contain concentrations of selenium 
considered by some researchers to be toxic to wildlife. The actual effects on the fishery are 
unknown, due to a lack of toxicity studies. 

Because of inadequate instream fishery flows from eastside tributaries to the San Joaquin River 
and high volumes of subsurface agricultural drainage water flows from the Grasslands area, 
upstream migrating adult salmon pass from the San Joaquin River into Mud and Salt Sloughs 

85 



instead of the Merced River to spawn. This situation has prompted expensive efforts to trap and 
artificially spawn adult fish and transport the eggs to the Merced River Fish Facility for hatching 
and rearing. In a future-without scenario, this situation could be expected to continue 
indefinitely. 

Several efforts have recently been initiated to address the inadequate instream fishery flows (for 
example, in the mainstem San Joaquin River between the Merced River and Friant Dam) and 
related environmental problems in the basin. Such efforts include the California Department of 
Water Resources' San Joaquin River Management Program, the U.S. Bureau of Reclamation's San 
Joaquin River Basin Resource Management Initiative, and litigation regarding renewal of 40-year 
water contracts from the Friant project. It is uncertain whether any of these efforts will provide 
flows in the mainstem San Joaquin River of adequate quantity and quality to support a viable 
fishery, including restoration of Chinook salmon runs. 

In addition, loading of selenium and other drainage-related contaminants into the Bay-Delta 
ecosystem would continue under the future-without alternative. It is unknown what effects, if any, 
long-term loading of these systems with such trace elements would have on the health of the 
fishery, on other water-dependent wildlife, or on humans consuming such animals. 

Public Health Effects 

The greatest risk to public health from the lack of a coordinated action to solve the drainage 
problem is likely to arise from increased use of conventional evaporation ponds for disposal of 
agricultural drainage water. Where bioaccumulation of trace elements occurs through the aquatic 
food chain, consumption of contaminated game would increase human exposure to elevated 
concentrations of these elements. Decommissioning of evaporation ponds might also pose 
occupational hazards from inhalation of airborne contaminants. 

Because ground- and surface-water quality in the valley will continue to deteriorate, potential 
human exposure to water contaminants will become greater. Future population growth and urban 
expansion projected for the San Joaquin Valley will bring people closer to all sources of 
agricultural drainage-water contaminants (air, soil, water, and biota) and thus reinforce the 
likelihood of adverse effects from exposure of such contaminants. 

Social Effects 

Farmland is expected to be abandoned more rapidly toward the end of the planning period. 
However, since the impacts would be spread over several decades, their effect upon farm 
operators, employees, and rural communities would permit adjustment that would moderate the 
cumulative social effects associated with the loss of productivity. 

While land is being abandoned, the value and marketability of drainage-affected agricultural land 
would slowly stagnate, while uncertainty about the future would grow. Without an integrated 
regional solution, individual farmers would have increasing difficulty acquiring financing for farm 
operations and installation of drainage management facilities. 

Patterns of land abandonment would likely be irregular, with farmers attempting to preserve the 
most productive lands for high-value crops and selecting less productive lands for on-farm 



86 



drainage disposal. The remaining irrigated lands would be used more intensively as lands with 
drainage problems were abandoned. Over time, the cropping pattern in the approximate 
1-million-acre drainage problem area would become less diverse, with production shifts toward 
less profitable salt-tolerant crops. Farmers with marginal technical capacity and financial 
resources would suffer the most severe consequences; many small and/or undercapitalized farm 
operations would go out of business. 

Those who farm lands without drainage problems could acquire a competitive economic 
advantage over those who farm lands with high water tables and associated high salinity, by 
realizing increases in land value and profitability. Nevertheless, the total agricultural production 
(and associated agribusiness) in the San Joaquin Valley would likely decline significantly from 
present levels. 

There would also be a significant conversion of farmland to alternative uses, either wildlife habitat 
or residential/commercial development. San Joaquin Valley towns within the drainage study area 
would become less dependent upon their traditional agricultural support base and more 
autonomous as fully developed small cities. Population expansion associated with the growth of 
valley communities would likely put greater pressures upon wildlife refuges and recreational lands. 

The current level of cooperation among water districts in water management activities could 
deteriorate as drainage conditions worsened in the valley. As the value of the assessment base of 
farmland dropped due to lower land values, water districts would be less able to take action to 
resolve drainage problems. The smaller districts would be more adversely affected (at least five of 
them in the drainage study area could lose more than 50 percent of their assessment base through 
land abandonment). Some water management districts might be forced to merge and/or 
centralize operations to meet growers' needs and would probably not be capable of resolving 
drainage problems without considerable assistance from other agencies. 

OPTIONS FOR DRAINAGE-WATER MANAGEMENT 

The Drainage Program has identified a broad range of individual structural and nonstructural 
management options, which analyses show have potential for helping to solve subsurface 
agricultural drainage and related problems in the San Joaquin Valley. Some 80 options, classified 
into seven categories, were identified and described in the Program's Preliminary Planning 
Alternatives report of August 1989. The options are the basic building blocks of the alternative 
plans. However, no single option will achieve all the desired results. Several of them, fitted 
together into a coordinated, comprehensive plan for action, could be effective in managing 
drainage problems. The mix of options will have to be varied to accommodate local and regional 
differences in drainage problems and opportunities for solution. Different mixes of options are 
emphasized in the alternatives described later in this chapter. The options shown through 
analysis to be most useful in drainage problem management at this time are briefly discussed in 
the following sections. 

Drainage- Water Source Control 

A first step in solving valley drainage problems is to reduce the production of potential drainage 
water; that is, to control drainage production at the source. Source control options encompass a 
broad array of measures to apply irrigation water more efficiently and to manage land and water 



87 



in ways that reduce the magnitude and adverse effects of drainage and drainage-related problems. 
Options included in the alternatives are: 

• Water conservation: 

Improve existing irrigation practices and/or adopt new irrigation methods. 

Improve irrigation scheduling. 

Improve management of irrigation systems. 

Manage the water table to increase its contribution to crop evapotranspiration. 

• Change in land use: 

Cease irrigation of lands that have high salinity and selenium concentrations in 
underlying shallow ground water and that are difficult to drain. 

Each of the alternatives presented later in this chapter includes some degree of source control. 
Water conservation and retirement of lands from irrigated agriculture are discussed separately as 
drainage management plan components. 

Ground- Water Management 

In some parts of the principal study area, water in the semiconfined aquifer above the Corcoran Clay 
(Figure 4) is of suitable quality for direct application in irrigation.(^) This water occurs in both the 
Sierran sediments and the Coast Range alluvium parts of the aquifer. Where there is an adequate 
vertical hydraulic connection between waterlogged lands and this deeper, usable ground-water zone, 
pumping from the zone may be used to lower the water table. Planned application of pumped water 
as a substitute for a portion of the surface-water irrigation supply could bring the system into 
hydrologic balance and stabilize the water table at a lower depth. This would make part of the 
surface-water supply currently required for that area available for other uses. 

Drainage- Water Treatment 

Various drainage-water treatment processes have been investigated at several levels of 
development. The goal of these investigations has been to identify methods of removing trace 
elements of concern (mainly selenium) from drainage water. 

These processes have not been investigated equally or developed to the same level of technology. A 
review of the capabilities and limitations of processes investigated was completed and is presented 
in Hanna, et al.. 1990. A few, such as anaerobic-bacterial treatment, high-rate algal ponds, and 
ferrous hydroxide, have advanced beyond laboratory bench-scale research. However, investigations 
of even these methods are incomplete, and more work with larger scale "pilot" or "prototype" 
plants is needed to establish technical performance and reliable cost estimates. Moreover, there 
has been no substantial operational experience with any drainage-water treatment process. The 
most promising new processes for selenium removal are biological processes. Of these, research is 
most advanced on the anaerobic-bacterial process. Research and demonstration are continuing on 
the physical and chemical removal of selenium, such as the work being done on iron filings at 
Panoche Water District, and this procedure should be pursued further. Reverse osmosis and other 
desalting methods are proven but high-cost methods. 



' Blending with other irrigation water supplies to make possible the use of saline ground water on crops normally 
grown in the drainage problem area was not included as an alternative plan component. 



88 




Irrigation water can be applied more efficiently by using 
shortened furrow lengths (upper left), drip systems (upper 
right), gated pipe (lower left), and microsprinklers (lower 
right). 



89 



Treatment of drainage water is not included in the alternatives because the uncertainties of their 
effectiveness and/or their high cost make investment in them a fiscal risk at this time. However, 
the Drainage Program recommends additional study of treatment processes because of their 
long-term potentials (see Chapter 1). 

Drainage- Water Reuse 

Of the various possible reuses of drainage water, irrigation (including salt-tolerant trees and 
halophytes), fish and wildlife habitat water supply, and solar ponds for energy production appear 
to have the greatest promise at this time. The options considered for the alternatives are: 

• Reuse of subsurface drainage water for agriculture: 

Reuse on very salt-tolerant crops having an upper permissible limit of 2,500 ppm 
TDS in water supply; cotton (after plant emergence), for example. 

Reuse on salt-tolerant trees having an upper permissible limit of 10,000 ppm TDS 
in water supply; eucalyptus trees, for example. 

Reuse on halophytes having an upper permissible limit of 25,000 ppm TDS in 
water supply; atriplex, for example. 

• Use of concentrated drainage water in solar ponds (from agricultural reuse options or 
from evaporation ponds) for energy production. 

• Use of drainage water for fish and wildlife habitat when there is very low toxic risk. 
Each alternative includes some amount of drainage-water reuse. 

Drainage-Water Disposal 

Drainage-water disposal options include: (1) Discharge to the San Joaquin River, with and 
without dilution; (2) discharge to evaporation ponds; (3) deep percolation into ground water; 
(4) injection into deep geologic formations; and (5) use for irrigation on the eastern side of the 
valley. The following are considered for inclusion in the alternatives at this time: 

• Discharge to the San Joaquin River without dilution (including use of portions of the 
San Luis Drain to convey drainage water to treatment or disposal areas). 

• Discharge to ponds to evaporate drainage water and concentrate dissolved 
constituents. 

• Deep percolation into the semiconfined aquifer. 

Westlands Water District continues to experiment with deep-well injection and, if successful, may 
use option (4), immediately above. 

Fish and Wildlife Measures 

Fish and wildlife measures have been developed that address the Drainage Program's goal to 
"protect, restore, and to the extent practicable improve fish and wildlife resources of the San 
Joaquin Valley." Options included here are those which could be undertaken in concert with 
other options to address drainage-related problems. Options for improvement of fish and wildlife 



90 



resources are discussed in the Drainage Program's Preliminary Planning Alternatives report. 
Options considered for inclusion in the alternatives at this time are: 

• Protection (in addition to the assumed enforcement of water-quality, wildlife, and 
other environmental laws): 

Modify evaporation pond design, construction, operation, and monitoring so that 
ponds are bird-safe or bird-free. 

Develop definite plans for evaporation pond closure when closure appears to be 
necessary or inevitable. 

Provide alternative habitat (including adequate water supplies) near evaporation 
ponds that require hazing because they are unsafe for birds. 

• Restoration: 

Flood and flush habitat with freshwater. 

Manage soil and vegetation to decontaminate wildlife habitat. 

• Substitute water supplies for fish and wildlife to replace contaminated drainage water. 
Substitute water would also improve protection and assist restoration. (These options 
must include modifications of existing supply or drainage systems to allow delivery of 
water to fish and wildlife areas directly, or by exchange arrangements.) 

Use water saved from source-control options (that is, on-farm water conservation 
and/or land retirement). 

Use wetland areas to seasonally store agricultural water supplies for release during 
April and May to improve fish habitat in the San Joaquin River. 

Use ground water produced by ground-water management options. 

Use nontoxic drainage water to produce saline wetlands. 

Institutional Changes 

Growers and private and public fish and wildlife managers operate within a framework of 
Federal, State, and local laws, policies, and practices. Some changes in the existing institutional 
framework may help solve drainage problems, directly or indirectly, by allowing implementation 
of plan components that otherwise might not be undertaken. The options listed here appear to be 
those most likely to be used in helping solve the drainage problem. A long list of potential 
institutional changes was provided and discussed in the Drainage Program's Preliminary Planning 
Alternatives report. Analysis of potential changes is provided in the Natural Heritage Institute 
report on institutional change (Thomas and Leighton-Schwartz, 1990). The primary options being 
considered are: 

• Use of tiered irrigation water pricing, or other types of financial incentives, by water 
districts, the Central Valley Project, or the State Water Project. 

• Drainage contribution surcharge on irrigation water. 

• Modification of water-transfer and water-marketing policy and laws. 

• Formation of regional drainage management entities that might be structured as 
special districts, joint powers authorities, or nonprofit mutual benefit cooperatives. 

91 



Evaluation of Options 

Before options are used in alternatives, it is necessary to: (1) Determine the geographical 
applicability of the options, and (2) evaluate their cost, performance, and impacts. The shallow 
ground water quality zones shown in Figure 18 are the units used for evaluation. 

Options are applied within the framework of objectives and standards shown in Table 7. The 
applicability of drainage management options to each of the drainage water quality zones, under 
either performance Level A or B, is displayed in Tables 15 and 16, respectively. Source control is 
applicable in every area. Discharge of drainage water to the San Joaquin River is applicable in 
the Northern Subarea and in two areas of the Grasslands Subarea. Salt-tolerant trees can be 
grown to transpire drainage water in 10 of the 16 areas. Trees cannot be grown in the other six 
areas because drainage water from field crops (water supply for trees) will exceed 10,000 ppm 
total dissolved solids (salt). Growing extremely salt-tolerant plants, such as saltbush, is not 
precluded in any area. Table 15 shows that, under performance Level A, land retirement may be 
applicable in some shallow ground-water areas where dissolved selenium is above 200 ppm. 
Table 16 shows that, under performance Level B, much more area is candidate for retirement 
when the criterion is lowered to 50 ppb. Existing evaporation ponds may be continued under 
both A and B performance levels, but only if they are bird-safe or can be made bird-free. The 
assumed safe level of selenium concentration for Levels A and B are 5 ppb and 2 ppb, 
respectively. In the ground-water management option, water may be pumped from the 
semiconfined aquifer when the thicknesses of suitable aquifer materials exceed 100 feet (Level A) 
or 200 feet (Level B) and the quality of the water produced is suitable for irrigation. 

The results of an evaluation of the options considered effective and available are presented in 
Table 17. The evaluation is based on uncertainty analyses, economic analyses, and standard 
impact assessment techniques. 

In addition to the restraints provided by the planning objectives, criteria, and standards given in 
Table 7, the evaluation of options in Table 17 should shape the extent to which a given option can 
be used in an alternative. Table 17 indicates that virtually all options have some limitations or 
produce an adverse effect on an important parameter of interest; for example, fish and wildlife, 
the economy, or the local community. Conversely, each option shows characteristics and effects 
beneficial to some interests. Judgment has to be exercised in determining the emphasis to place 
on a given option, considering the balance of effects. The lowest-net-cost option is sought, but not 
at the expense of significant risk to other interests. 

The evaluation reveals that, although some options are cost-effective, certain risks must be 
acknowledged. For example, the feasibility of discharge to the San Joaquin River might be 
affected significantly by possible future changes in water-quality regulations. Similarly, reuse 
might be affected by significant adverse effects on wildlife. In contrast, the risks of reuse of 
drainage water are less than the risks of evaporation ponds, and reuse has a comparative cost 
advantage. (Measures considered promising to make evaporation ponds bird-free or bird-safe are 
included in cost estimates.) Therefore, it is concluded that, comparatively, use of evaporation 
ponds should be minimized and reuse maximized. 



92 



Table 15. APPLICABILITY OF DRAINAGE MANAGEMENT OPTIONS 
LEVEL "A" PERFORMANCE STANDARDS 



Subareas 

and 

Water Quality 

Zones 


Drainage 
Source 
Control 


San 

Joaquin River 

Discharge' 


Salt- 
Tolerant Trees 


Halo- 
phytes 


Land 
Retirement' 


Existing 

Evaporation 

Ponds 


New 

Evaporation 

Ponds^ 


Ground Water 
Management* 


Grasslands 
A 

B 

C 

D' 


X 
X 

NR 
NR-W 


Y(15,5k AF) 

Y(4.0k AF) 

X 

NR-R 


X 
X 

NR 
NR-W 


X 
X 

NR 
NR-W 


Y(37.4k Ac) 

NA(<200ppbSe) 

NR 

NR-W 


Y(0.1kAc.) 

NA 

NR 

NR-W 


NA(>5ppbSe) 
X 

NR 
NR-W 


Y(25k Ac) 

Y(51kAc.) 

NR 

NR-W 


Westlands 
A 

B 

C 

D 


X 
X 
X 
X 


NA 
NA 
NA 
NA 


X 

NA( > 10k ppm TDS) 
X 
X 


X 
X 
X 
X 


Y(7.6kAc.) 

Y(7.0k Ac) 

NA(<200ppbSc) 

NA(<200ppbSe) 


NA 

Y(0.1kAc.) 

NA 
Y(0.4k Ac.) 


NA(>5ppbSe) 
NA(>5ppbSe) 
NA(>5ppbSe) 
NA(>5ppbSe) 


Y(9k Ac.) 

NA{<100fl. Ihick) 

Y(69k Ac.) 

Y(43k Ac.) 


Tulare 
A 

B 

C 

D 

E 


X 
X 
X 

X 
X 


NA 
NA 

NA 
NA 
NA 


X 

NA( > 10k ppm TDS) 

X 
NA( > 10k ppm TDS) 

X 


X 
X 
X 
X 
X 


NA(<200ppbSe) 
NA(<200ppbSe) 
NA(<200ppbSe) 
NA(<200ppbSe) 
NA(<200ppbSe) 


Y(0.5k Ac) 
Y(3.6k Ac.) 
Y(0.2k Ac.) 
Y(0.3k Ac.) 
Y(0.3k Ac.) 


X 

NA(>SppbSe) 

NA(>5ppbSe) 

NA(>5ppbSe) 

X 


Y(34k Ac.) 

NA(< 100 ft. thick) 

NA(< 100 ft. thick) 

Y(38k Ac.) 

Y(100k.'\c) 


Kern 
A 

B 

C 

D 


X 

X 
X 
X 


NA 
NA 
NA 
NA 


NA( > 10k ppm TDS) 
NA( > 10k ppm TDS) 

X 
NA( > 10k ppm TDS) 


X 
X 
X 
X 


Y(2.2 Ac.) 
NA(<200ppbSe) 
NA( < 200 ppb Se) 

Y{0.9k Ac.) 


Y( 1.3k Ac.) 

NA 
Y(0.2k Ac.) 
Y(0.2k Ac ) 


NA(>5ppbSe) 
NA(>5ppbSe) 

X 
NA(>5ppbSe) 


NA(<100fI. thick) 
NA(< 100 ft. thick) 
NA(<100ft. thick) 
NA(<100ft. thick) 



X 

Y 

NA 

NR 



.Applicability of option depends on the selenium cntenon (mean monthly concentration of 8 ppb) and a critical water year hydrology (for example. 1986-87) 

for San Joaquin River near Newman, Selenium load is expected to decrease up to 50% by 2040 as a result of the gradual removal of selenium from the 

shallow ground water and soils due lo the leaching prtxcss. 

The selenium concentration of 200 ppb in the shallow ground water was used to select lands on which irrigated agriculture would be discontinued. 

New evaporation ponds can be used when drainage water selenium concentration exceeds 5 ppb and is <50 ppb only if ponds can be made bird-safe or 

bird-free Measures necessary to make ponds bird-free will include alternative habitat with an adequate firm water supply. 

Option limited by the aquifer thickness and quality of the ground water (less than 1.250 ppm TDS). 

Managed wildlife wetland area. 

Option IS applicable without any limitation in its application. 

Option is applicable but limited to the quantities and units included in the parentheses. 

Option not applicable because it fails to meet the performance standard in parentheses (see Table 7) or not physically available in the instances of 

discharge to the San Joaquin River 

Option not suggested because increased conservation with resulting increased salinity will reduce the likelihood that drainage water can be used for wetland habitat. 



NR-W Option is not applicable since shallow ground water within wetlands is not a problem; it benefits waterfowl. 



93 



Table 16. APPLICABILITY OF DRAINAGE MANAGEMENT OPTIONS 
LEVEL "B" PERFORMANCE STANDARDS 



Subareas 

and 

Water Quality 

Zones 


Drainage 
Source 
Controi 


San 
Joaquin 

River 
Discharge' 


Sail- 
Tolerant Trees 


Halo- 
phyles 


Land 
Retirement' 


Existing 

Evaporation 

Ponds 


New 

Evaporation 

Ponds' 


Ground Water 
Management* 


Grasslands 
A 

B 

C 

D' 


X 
X 

NR 
NR-W 


Y(4.5k AF) 

Y(4.0k AF) 

X 

NR-R 


X 
X 

NR 
NR-W 


X 
X 

NR 
NR-W 


Y(90 Ok Ac.) 

Y(0.3k Ac.) 

NR 

NR-W 


Y(OlkAc) 

NA 

NR 

NR-W 


NA(>5ppbSe) 
X 

NR 
NR-W 


Y(17kAc) 

Y(16kAt) 

NR 

NR-W 


Westlands 
A 

B 

C 

D 


X 
X 
X 
X 


NA 

NA 
NA 
NA 


X 

NA( > 10l< ppm TUS) 
X 
X 


X 
X 
X 
X 


Y(23.2k Ac.) 

Y(39 4k Ac ) 

Y(57.9k Ac.) 

NA(<50ppbSe) 


NA 
Y(0 1kAc.) 

NA 
Y(a4k Ac) 


NA(>2ppbSe) 
NA(>2ppbSe) 
NA(>2ppbSe) 
NA(>2ppbSe) 


NA(< 200 fl. thick) 

NA(< 200 ft. thick) 

Y(54k Ac) 

Y(31kAc) 


Tulare 
A 

B 

C 

D 

E 


X 
X 
X 
X 
X 


NA 
NA 
NA 
NA 

NA 


X 

NA( > lOlt ppm TDS) 

X 
NA( > 10k ppm TDS) 

X 


X 
X 
X 
X 
X 


NA(<50ppbSe) 
NA(<50ppbSe) 
NA( < 50 ppb Se) 
N.A(<50ppbSe) 
NA(<50ppbSe) 


Y(a5k Ac) 
Y(3 6k Ac.) 
Y(0.2k Ac) 
Y(0 3k Ac) 
Y(0.3k Ac) 


X 

NA(>2ppbSe) 

NA(>2ppbSc) 

NA(>2ppbSe) 

X 


Y(2IkAc) 

NA(<2()0ft thick) 

NA(<2()0fl. thick) 

Y(33k Ac) 

Y(95k Ac) 


Kern 
A 

B 

C 

D 


X 
X 
X 
X 


NA 
NA 
NA 
NA 


NA( > 10k ppm TDS) 
NA( > 10k ppm TDS) 

X 
NA( > 10k ppm TDS) 


X 
X 
X 

X 


Y(219 5 Ac) 
NA( < 50 ppb Se) 
NA( < 50 ppb Se) 

Y(23.6k Ac) 


Y( 1.3k Ac) 

NA 
Y(0.2kAc) 
Y(0.2k Ac) 


NA(>2ppbSe) 
NA(>2ppbSe) 

X 
NA(>2ppbSe) 


NA(< 200 ft. thick) 
NA(<200ft thick) 
NA(< 200 ft thick) 
NA(< 200 ft thick) 



X 

Y 
NA 

NR 



Applicability of option depends on the selenium cntenon (mean monthly amcentration of 2 ppb) and a critical water year hydrology (for example. 1986-87) 

for San Joaquin River near Newman. Selenium load is expected to decrease up lo 50% by 2040 as a result of the removal of salts from the shallow ground 

water and soils due to the leaching process. 

The selenium concentration of 50 ppb in the shallow ground water was used to select lands on which irrigated agriculture would be discontinued. 

New evaporation ponds can be used when drainage water selenium concentration exceeds 2 ppb and is <50 ppb only if ponds can be made bird-safe 

or bird-free. Measures necessary to make ponds bird-free will include alternative habitat with an adequate firm water supply. 

Option limited by the aquifer thickness and quality of the ground water (less than 1,250 ppm TDS). 

Managed wildlife wetland area. 

Option is applicable without any limitation in its application. 

Option is applicable but limited lo the quantities and units included in the parentheses. 

Option not applicable because it fails to meet the performance standard in parentheses (see lable 7) or is not physically available in the instances of discharge 

to the San Joaquin River. 
Option not suggested because increased conservation with resulting increased salinity will reduce the likelihood that drainage water can be used for wetland habitat. 



NR-W Option IS not applicable since shallow ground water within wetlands is not a problem: it benefits waterfowl. 



94 



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97 



PLANNING ALTERNATIVES 

Three planning alternatives were formulated that emphasize: (1) The conservation and reuse of 
agricultural water, (2) the extraction of irrigable water from deep within the semiconfmed aquifer 
to lower the near-surface water table in waterlogged land areas, and (3) the retirement of 
irrigated agricultural lands overlying shallow ground water that contains greatly elevated 
concentrations of dissolved selenium. Two levels of performance, A and B, were applied to each 
alternative. These alternatives were devised to compare potential reduction in problem water 
volumes, if differing options for managing the drainage problem were emphasized. Four 
strategies involving major options that were employed in formulating the planning alternatives are 
discussed in the following sections. 

Drainage Management Strategies Underlying the Alternatives 

Four main strategies for management of drainage problems have emerged during the course of 
this study. These are source control, drainage water reuse, ground-water management, and land 
retirement. Each strategy is used to reduce problem water volumes in the three planning 
alternatives. 

Source Control 

The major source of recharge to the ground water system and subsequent production of drainage 
water is the portion of applied irrigation water that percolates past the crop root zone into the 
semiconfined aquifer. Some water must pass the root zone to leach salts and maintain soil 
productivity. Unnecessary deep percolation can be reduced mainly through better management of 
irrigation systems. 

Current average deep percolation in the study area is estimated to vary from about 0.90 to 1.05 
feet (Burt and Katen, 1988; D.G. Swain, 1990). Assuming 0.3 foot is the minimum amount 
necessary to achieve required salt leaching and is also the amount moving downward through the 
Corcoran Clay, nonbeneficial deep percolation contributes 0.60 to 0.75 foot annually to potential 
problem water. 

Higher irrigation efficiencies leading to reduced deep percolation can be achieved by individual 
options or combinations of options. The most effective of these appear to be: (1) Improving 
management of irrigation systems, (2) improving present irrigation practices (for example, 
shortening furrows and using tailwater return systems, thus increasing uniformity of water 
application) and adopting new irrigation methods, and (3) improving irrigation scheduling. These 
and other options are discussed more fully in the Drainage Program's 1989 report. Preliminary 
Planning Alternatives. 

Not all potential problem water is generated by deep percolation at a given site. Some lateral 
movement of water from upslope areas may also contribute to drainage problems downslope. 
This contribution varies considerably, depending upon local geologic and hydrologic conditions, 
but a drainage problem most often arises from practices and conditions at the site. Reduction of 
deep percolation, even in areas without present drainage problems, can help reduce the long-term 
regional drainage problem. 



98 



Drainage-Water Reuse 

The concept of drainage-water reuse is shown in Figure 19. The objective is to reduce the volume 
of drainage water requiring ultimate disposal by reusing it on progressively more salt-tolerant 
crops. The volume of water would be reduced by evapotranspiration. with dissolved constituents 
such as salt, boron, and selenium becoming more concentrated and probably easier to manage in 
an environmentally safe manner. Volume reduction through reuse would substantially reduce 
disposal costs and treatment costs, if treatment became necessary. 

The initial good-quality water supply would be used to grow high-value, salt-sensitive crops, such 
as vegetables. Drainage water captured in the tile drainage system under these lands would be 
collected and pumped into a local distribution system to become the water supply for a 
salt-tolerant field crop, such as cotton. (If this were not practicable, the drainage could go 
directly to trees.) 

Drainage from these fields would become the water supply for salt-tolerant trees, such as 
eucalyptus. Trees would be used at this stage, not only because of their tolerance to salt, but also 
because they are capable of high transpiration rates (about 5 feet of water per year). Finally, 
drainage from the trees would be used on halophytes that grow in extremely saline conditions, 
such as atriplex or salt bush. Even halophytes have limits for total dissolved salts and certain 
other substances, such as boron. The levels of boron and total salinity of water in the root zone 
must be monitored and the fields drained to maintain growth. 

At that stage of the reuse process, the extremely concentrated drainage water must be disposed 
of, or it could be stored in small evaporation ponds, treated to remove toxicants, or, when 
possible, injected into deep geologic formations. Water and salts from the evaporation ponds 
could also be used at solar-energy ponds or cogeneration facilities. 

Figure 20 illustrates pond configurations that might be used as part of a drainage water 
management system. The standard evaporation pond shown would be similar to ponds 
traditionally used in the valley, except that it would be improved with steepened sides and greater 
depths to reduce wildlife food supplies and discourage wildlife use. In contrast to traditional 
ponds, the new standard pond would be smaller so that birds could be more effectively hazed 
from it to alternative safe wetland habitat (not shown on sketch) that would be provided in the 
vicinity. 

The nontoxic evaporation pond would also provide safe wildlife habitat and would be designed for 
that purpose. The northern portion of the Tulare Subarea (Kings River Delta) appears to be an 
area in which drainage water could evaporate in ponds that would be safe for wildlife use. 

The accelerated rate ponds would employ mechanical devices to increase the rate of evaporation. 
Used in a facility in El Paso, Texas, the device shown here reduced the volume of applied water by 
about 25 percent in one pass through the system. Use of an accelerated evaporation system 
greatly reduces pond area, but it increases the cost. 

The solar pond shown would use very concentrated drainage water from either the standard or 
accelerated pond. The area covered by a solar pond would be small. This type of pond does not 
appear to attract birds. The value of the electrical energy generated would offset some of the total 
drainage system costs. 

99 



Figure 19. THE CONCEPT OF DRAINAGE-WATER REUSE 



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101 



Figure 21. THE CONCEPT OF GROUND-WATER MANAGEMENT 



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The major benefit from the reuse strategy is the reduction of drainage-water volume. Volume 
could be reduced as much as 80 to 95 percent, depending on the crops, soils, and management of 
the system. A reduction in drainage-water volume translates to lower cost in final drainage-water 
management. 

Ground-Water Management 

The concept of ground-water management is to pump water, generally for irrigation, from the 
semiconfined aquifer above the Corcoran Clay to lower near-surface saline water tables 
(illustrated in Figure 21) and create a hydrologic balance that will keep the shallow water table 
below the crop root zone. In an unplanned manner, this strategy is currently being applied, to a 
minor extent, in the drainage problem area because some 2 million acre-feet of ground water is 
extracted annually from westside aquifers to supplement surface-water supplies. Although most 
of the pumping is from below the Corcoran Clay, the stress on the hydrologic system helps 
alleviate the subsurface drainage problem by providing storage space for deep percolation. 

In this strategy, the ground water extracted would be in addition to present extractions, and would 
be designed specifically for each drainage problem area in which it was applicable. Wells would 
be perforated to produce water only from selected zones of the semiconfined aquifer. This 
method would be technically feasible only if all the following conditions existed in the subsurface 
aquifers under the drainage problem area: (1) Adequate vertical hydraulic interconnection 



102 



between the deep aquifer and the waterlogged surface lands (not applicable to the Tulare lakebeds 
where thick clays are present); (2) a sufficient volume of water in the deep aquifer to allow 
withdrawal for a reasonable period of time (for example, 20 years); and (3) a production (from the 
well) water quality of less than 1,250 ppm TDS, so it may be used for agricultural irrigation. 
Reconnaissance-level geohydrologic investigations indicate that these conditions probably exist 
beneath those parts of drainage problem areas shown in Figure 12. 

Several aspects of this strategy need to be recognized as potentially limiting its overall feasibility, 
even though the controlled pumping that would occur under the strategy could be an 
improvement over existing pumping conditions. First, the periods during which wells must be 
pumped to lower the water table to the required depth and the period in which they are pumped 
to supply water for irrigation or other beneficial uses may not correspond. Second, the 
application of this alternative might be viewed as a planned degradation of ground water. This 
interpretation might be reached, even though the present extent of ground-water pumping 
produces a regional hydraulic stress that is causing water passing the root zone to move 
downward at an annual rate of 1 to 3 feet vertically, transporting with it accumulated salt, boron, 
selenium, and other substances. Third, if this alternative were to be economically feasible, the 
aquifer must be capable of producing water suitable for beneficial uses for at least 20 years. 

Although recent study has removed considerable uncertainties (Schmidt, 1988 and 1989; Quinn, 
1990; CH2M Hill, 1990; Phillips, 1990), an additional significant limiting factor is the continuing 
lack of adequate geohydrologic information on ground-water systems in some parts of the 
drainage problem area. 

Land Retirement 

The essential strategy of land retirement is to stop irrigating lands with poor drainage 
characteristics beneath which now lies shallow ground water so contaminated with selenium (and 
other substances) that drainage would be extremely difficult and the water produced would be 
costly to manage. Hydrologic investigations (Gilliom, et al., 1989b) indicate that, if a substantial 
land area (say, + 5,000 acres) were retired from irrigation, the shallow water table beneath those 
lands would drop. To some extent, instead of contributing to their contamination, the dewatered 
area beneath the retired lands would then become a sink to receive some contaminated water 
from adjacent lands. Figure 22 illustrates how land retirement would lower ground-water levels. 

The feasibility of this strategy hinges on the existence of shallow ground-water areas in which 
concentrations of selenium are much greater than those of surrounding areas. Figure 23 shows 
areas in which selenium concentrations in shallow ground water are more than 50 and 200 parts 
per billion. Areas over 200 parts per billion are considered to be "hot spots" and special 
candidates for retirement. The feasibility of land retirement also may depend on the existence of 
compensating benefits in the form of overall reduced costs of handling the drainage problem 
regionally, or in economic return to landowners from the sale or lease of the water supply no 
longer used for irrigation. 

A related aspect of land retirement is that it could be considered a land reserve and, if at some 
future time, the problem necessitating retirement were to be resolved, the land could be used 
again for irrigated agriculture. 

103 



Figure 22. THE CONCEPT OF LAND RETIREMENT 







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104 



Figure 23 

AREAS OF HIGHEST OBSERVED SELENIUM CONCENTRATIONS 
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105 



Description of Alternatives 

The following alternatives are analyzed and evaluated to subarea scope and detail. 

Northern Subarea 

Alternatives for problem water reduction were not prepared for the Northern Subarea because 
two factors that tend to motivate major changes in management of drainage problems are largely 
missing in this part of the valley. First, the shallow ground water is of relatively good quality and 
low in concentrations of dissolved gypsum, a substance that contributes greatly to problems of 
westside salinization of soil and ground water (D.G. Swain, 1990). 

Second, growers in the Northern Subarea are solving their drainage problems by draining their 
land and discharging about 20,000 acre-feet per year to the San Joaquin River. If water-quality 
objectives on the river do not change materially, growers would likely continue discharging to the 
river. 

In addition to controlled subsurface drainage water, the San Joaquin River also receives about 
100,000 acre-feet of ground water seepage annually from the Northern Subarea (CH2M Hill, 1988), 
an unknown portion of which is related to irrigation water application. Because of the large 
volume, this flow contributes about 25 percent of the annual salt load flowing into the San 
Joaquin River at Vernalis, primarily during low flows. 

Nishimura and Baughman (1989) have considered this phenomenon and remedial actions that 
might be both possible and necessary if more strict salt objectives were set for the San Joaquin 
River. One of the concepts mentioned prominently is a line of shallow wells that would be 
pumped during high river flows to evacuate the shallow ground water and create additional 
storage space for drainage water that would otherwise seep into the river during low-flow periods. 
Hydraulic and engineering studies conducted by the U.S. Bureau of Reclamation were reviewed 
by D.G. Swain (1990), who concludes that the concept of seasonal evacuation to halt the seepage 
(which could pose a problem during low flows) would not be effective because the San Joaquin 
River lacks the capacity to assimilate salt in most high-flow seasons. There would simply be too 
few opportunities to pump the interceptor wells because of the limited number of days in which 
the river has assimilitative capacity. 

If measures were to be adopted within the subarea to lower the shallow water table adjacent to 
the San Joaquin River, these could reduce some of the salt load to the river because more salt 
would be stored in ground water. Two measures that are technically available are: (1) Improving 
on-farm water application to reduce deep percolation to ground water, and (2) changing the 
present pattern of surface- and ground-water use to greatly increase the volume of ground water 
extracted. Presently, only an estimated 30,000 acre-feet per year are pumped from the combined 
semiconfined and confined aquifers. (In the Northern Subarea, the aquifers are highly 
interconnected through gravel-packed and multiple-zone wells.) At present, about 94 percent of 
the agricultural water supply in the Northern Subarea is obtained from the combined sources of 
the San Joaquin River and the Delta-Mendota Canal. Substituting ground water pumped from 
below the irrigated area for a portion of this imported surface water would lower the water table 
and reduce seepage to the San Joaquin River. However, the subsurface drainage that would be 
discharged to the river would become more saline. 



106 



Grasslands Subarea 

Figure 24 shows how various options would be combined to reduce problem water in the three 
planning alternatives. When read horizontally, the graphs show the effect on each option resulting 
from a shift from Level A to Level B performance standards. When read vertically, they show the 
effect on each option as the emphasis is changed from source control to ground-water 
management to land retirement. (Graphs are provided for this purpose in each subarea that 
follows.) Each Grasslands planning alternative includes the continued use of the San Joaquin 
River for disposal of some drainage water, although volumes would be reduced 15 to 20 percent 
under Level B selenium criteria, compared to the existing Level A criteria. 

Table 18 shows major features of Grasslands Subarea planning alternatives. Under the 
alternatives emphasizing source control, the maximum water conservation from source control 
increases from about 30,000 acre-feet per year in 2000 to 50,000 acre-feet per year in 2040. Source 
control, featuring available water conservation technologies (such as shortening furrows and using 
a tailwater return system), is included only in water quality zones A and B (Figure 18), where it 
would reduce the volume of problem water by 30 to 40 percent, depending upon the criteria. 
Source control would not be applied in water quality zone C and 50 percent of Zone B (where 
there are some problems with waterlogging) because that drainage water is considered reusable 
for irrigating, managing wetlands, and/or increasing flow and improving quality of the San 
Joaquin River. 

Drainage water would be reused under all alternatives. The maximum reuse under the source 
control alternative would require from 3,000 to 6,000 acres of salt-tolerant trees and halophytes by 
2000 and 2040, respectively. 




Wetlands In the Grasslands Subarea, which are laced with waterways, are flooded during 
the fall and winter waterfowl migration season. 



107 



Figure 24 
PROBLEM WATER REDUCTION 

GRASSLANDS SUBAREA 



150 


LEVEL "A" 




SOURCE CONTROL EMPHASIS ^ 




f^>^ SOURCE CONTROL 


100- 




/ ^ "^SE 


50- 


/<^^^-^^^^^^ 




SAN JOAQUIN RIVER 


0- 


' 1 1 1 1 1 



LEVEL "B" 

SOURCE CONTROL EMPHASIS 




DISCHARGE TO 
SAN JOAQUIN RIVER 



1990 



2040 1990 



2040 



03 

(U 



o 

< 

o 
o 
o 



< 



O 

> 



150 




GROUND WATER MANAGEMENT 
EMPHASIS 




DISCHARGE TO 
SAN JOAQUIN RIVER 



GROUND Vi/ATER MANAGEMENT 



1990 



2040 1990 



2040 



150 



100- 



LAND RETIREMENT 
EMPHASIS 




LAND RETIREMENT 
EMPHASIS 




LAND RETIREMENT 



1990 



YEARS 



2040 1990 



2040 



YEARS 



NOTE: Actions that reduce problem water less than 5000 acre -feet 
annually are not shown, but are discussed in the text. 



108 



Table 18. MAJOR FEATURES OF GRASSLANDS SUBAREA PLANNING ALTERNATIVES 

In 1,000s 



Performance 

.evel and Plan 

Emphasis 


Shallow 

Ground 

Water 

Area' 


Land 
Af- 
fected^ 


Problem 

Water 

Volume' 


Con- 
served- 
Water* 


Land Re- 
using 
Drainage' 


Land 
Re- 
tired* 


Land 
Overly- 
ing GW 
Pump- 
ing' 


Area of 
Existing 
Evapo- 
ration 
Ponds 


Area of 

New 
Evapo- 
ration 
Ponds 




Acres 


Acres 


Acre-feet 


Acre-feet 


Acres 


Acres 


Acres 


Acres 


Acres 


A-2000 




















Jource Control 


218.0 


116.0 


86.5 


30.1 


3.1 


0.0 


0.6 


0.1 


0.0 


Ground Water 


218.0 


116.0 


86.5 


29.4 


1.6 


1.9 


8.9 


0.1 


0.0 


Management 




















Land 


218.0 


116.0 


86.5 


26.4 


2.1 


10.7 


0.7 


0.1 


0.0 


Retirement 




















A-2040 




















Source Control 


218.0 


196.0 


147.0 


53.6 


3.1 


0.0 


0.6 


0.1 


0.0 


Ground Water 


218.0 


196.0 


147.0 


23.8 


2.3 


0.0 


60.8 


0.1 


0.0 


Management 




















Land 


218.0 


196.0 


147.0 


26.6 


2.8 


32.3 


0.8 


0.1 


0.0 


Retirement 




















B-2000 




















>ource Control 


218.0 


116.0 


86.5 


30.1 


5.4 


0.0 


1.2 


0.1 


0.0 


Ground Water 


218.0 


116.0 


86.5 


30.1 


5.4 


0.0 


1.2 


0.1 


0.0 


Management 




















Land 


218.0 


116.0 


86.5 


22.1 


3.7 


23.0 


0.2 


0.1 


0.0 


Retirement 




















B-2040 




















Source Control 


218.0 


196.0 


147.0 


53.6 


5.8 


0.0 


1.3 


0.1 


0.0 


Ground Water 


218.0 


196.0 


147.0 


53.6 


5.8 


0.0 


1.3 


0.1 


0.0 


Management 




















Land 


218.0 


196.0 


147.0 


13.8 


3.0 


70.2 


0.7 


0.0 


0.0 


Retirement 





















Irrigated land area with a depth to shallow ground water less than 5 feet. 

That portion of shallow water areas drained. 

The forecasted annual drainage volume that must be managed; drained land x 0.75 acre-feet per acre of deep percolation 

Water supply conserved by on-farm water conservation measures and management practices on problem water lands. 

Acreage in trees and halophytes. 

Lands targeted for retirement from irrigated agriculture (excluding lands designated for other uses). 

Land area where pumping from the semiconfined aquifer is used to lower shallow water table below crop root zone. 



109 



Because of geohydrologic conditions, opportunities for deep pumping of the semiconfined aquifer 
are limited to about 60,000 acres, largely in problem zone A. No new evaporation ponds would be 
included with any alternative. 

Under the land retirement alternative, retirement of irrigated land would be greater under Level B 
criteria and would increase from about 23,000 to 70,000 acres between 2000 and 2040. 

Westlands Subarea 

Figure 25 shows how various options would be combined to reduce problem water in the three 
planning alternatives. Each planning alternative places major reliance on source control for 
reducing problem water — up to a maximum of about 60 percent in 2040, under the source 
control alternative. 

Table 19 shows major features of Westlands Subarea planning alternatives. The maximum water 
conservation from source control would be 38,000 acre-feet annually by 2000, and 92,000 acre-feet 
annually by 2040, under either performance Levels A or B. 

Reuse of drainage water is a major feature of all alternatives for the Westlands Subarea. Under 
maximum reuse, 9,000 to 14,000 acres of trees and halophytes would be used to reduce problem 
water volume in 2000 and 2040, respectively. 

Subsurface physical conditions most strongly favor deep pumping from the semiconfined aquifer 
to lower shallow ground-water levels in water quality zones C and D (Figure 18). Level A criteria, 
ground-water management alternative, shows the area of maximum pumping would increase from 
about 26,000 acres in 2000 to 107,000 acres in 2040. 

Under Level B criteria for the land retirement alternative (all shallow ground-water areas above 
50 ppb selenium), 12,000 acres would be retired from irrigation by 2000 and 107,000 acres by 2040. 
In contrast to areas suitable for ground-water management in the southeastern part of Westlands 
Subarea, areas that fit the criteria for land retirement are located primarily in the northern part. 
No new evaporation ponds would be included under any alternative. 



110 



Figure 25 
PROBLEM WATER REDUCTION 

WESTLANDS SUBAREA 



200 n 


LEVEL "A" 

SOURCE CONTROL EMPHASIS 




IbU- 
100- 


SOURCE CONTROL 


50 - 


// GROUND WATER MANAGEMENT 


REUSE 


0_ 





LEVEL -B- 



SOURCE 


CONTROL 

GROUND 


EMPHASIS 


SOURCE 




CONTTiOL 


WATER MANAGEMENT 


REUSE 






■ 


i 



1990 



2040 1990 



2040 



o 
< 

o 
o 
o 



< 



O 
> 



,;uu- 


GROUND WATER 


MANAGEMENT 




EMPHASIS 




Ibll- 








^^ SOURCE CONTROL 


100- 




^ REUSE 


50 - 




GROUND WATER MANAGEMENT 







\ \ 1 1 



GROUND WATER 


MANAGEMENT 




EMPHASIS 






SOURCE CONTROL 


/^ 




REUSE 




GROUND 


WATER MANAGEMENT 



1990 



2040 1990 



2040 



200 



150 



100 



50 



LAND RETIREMENT 
EMPHASIS 


GROUND 


SOU 




RCE CONTROL 


WATER 


REUSE 

MANAGEMENT 






_— 




— 1 1 






-T » 1 



LAND RETIREMENT 
EMPHASIS 




1990 



LAND RETIREMENT 2040 1990 



YEARS 



YEARS 



2040 



NOTE: Actions that reduce problem water less than 5000 acre-feet 
annually are not shown, but are discussed In the text. 



Ill 



Table 19. 



MAJOR FEATURES OF WESTLANDS SUBAREA PLANNING ALTERNATIVES 

In 1 ,000s 





Shallow 

Ground 

Water 

Area' 












Land 


Area of 


Area of 


Performance 


Land 


Problem 


Con- 


Land Re- 


Land 


Overly- 


Existing 


New 


Level and Plan 


Af- 


Water 


served- 


using 


Re- 


ing GW 


Evapo- 


Evapo- 


Emphasis 


fected' 


Volume' 


Water* 


Drainage^ 


tired* 


Pump- 


ration 


ration 














ing' 


Ponds 


Ponds 




Acres 


Acres 


Acre-feet 


Acre-feet 


Acres 


Acres 


Acres 


Acres 


Acres 


A-2000 




















Source Control 


170.0 


108.0 


81.1 


37.9 


9.4 


0.0 


3.5 


0.1 


0.0 


Ground Water 


170.0 


108.0 


81.1 


37.9 


5.8 


0.7 


26.2 


0.1 


0.0 


Management 




















Land 


170.0 


108.0 


81.1 


34.4 


8.4 


10.2 


3.1 


0.1. 


0.0 


Retirement 




















A-2040 




















Source Control 


227.0 


205.0 


153.9 


92.4 


13.8 


0.0 


5.1 


0.5 


0.0 


Ground Water 


227.0 


205.0 


153.9 


62.4 


7.8 


0.0 


106.9 


0.5 


0.0 


Management 




















Land 


227.0 


205.0 


153.9 


85.7 


12.5 


14.5 


4.6 


0.3 


0.0 


Retirement 




















B-2000 




















Source Control 


170.0 


108.0 


81.1 


37.9 


9.4 


0.0 


3.5 


0.3 


0.0 


Ground Water 


170.0 


108.0 


81.1 


37.9 


6.2 


0.0 


22.0 


0.5 


0.0 


Management 






« 














Land 


170.0 


108.0 


81.1 


33.9 


8.5 


11.5 


2.7 


0.3 


0.0 


Retirement 




















B-2040 




















Source Control 


227.0 


205.0 


153.9 


92.4 


13.6 


0.0 


5.7 


0.1 


0.0 


Ground Water 


227.0 


205.0 


153.9 


56.6 


10.7 


0.0 


97.8 


0.5 


0.0 


Management 




















Land 


227.0 


205.0 


153.9 


39.9 


7.2 


106.9 


2.0 


0.0 


0.0 


Retirement 





















1 Irrigated land area with a depth to shallow ground water less than S feet. 

2 That portion of shallow water areas drained. 

3 The forecasted annual drainage volume that must be managed: drained land x 0.75 acre-feet per acre of deep percolation 

4 Water supply conserved by on-farm water conservation measures and management practices on problem water lands. 

5 Acreage in trees and halophytes. 

6 Lands targeted for retirement from irrigated agriculture (excluding lands designated for other uses). 

7 Land area where pumping from the semiconfined aquifer is used to lower shallow water table below crop root zone. 



112 



Tulare Subarea 

Figure 26 shows how various options would be combined in the Tulare Subarea to reduce 
problem water. Table 20 shows major features of Tulare Subarea planning alternatives. All plans 
include major reliance on source control for reducing problem water, up to a maximum of about 
60 percent in 2040 under the source control alternative. The maximum water conservation 
through source control would be 44,000 acre-feet annually by 2000 and 156,000 acre-feet annually 
by 2040, under the source control alternative. 

Reuse of drainage water is a major feature of the alternatives presented for the Tulare Subarea. 
Under the maximum reuse option, from 11,000 to 23,000 acres of trees and halophytes would be 
used in 2000 and 2040, respectively. 

Conditions favorable for deep pumping of the semiconfined aquifer occur largely in areas 
influenced by the Kings River Delta: water quality zones A, D, and E (Figure 18). The planning 
criteria would allow pumping under a maximum of about 20,000 acres in 2000 and 135,000 acres 
in 2040. Ground-water management or evaporation ponds may be used in zone E, where drainage 
water is generally very low in dissolved selenium. No new evaporation ponds are included in any 
alternative. Further study may reveal that evaporation ponds in the South Kings River Delta 
(zone E) would be bird-safe because of low contaminant concentrations in drainage water. 

No shallow ground water in the Tulare Subarea is known to be high enough in selenium 
concentration to exceed the 200 ppb planning criterion for land retirement. Alternatives 
emphasizing land retirement are included, but they are almost identical to the source control 
alternatives. 

Kern Subarea 

Figure 27 shows how various options would be combined in the Kern Subarea to reduce problem 
water in the three planning alternatives. Table 21 shows major features of the planning 
alternatives. All plans include major reliance on source control for reducing problem water, up to 
a maximum of about 55 percent in 2040, under the source control alternative. The maximum 
water conservation that would occur through source control would be 21,000 acre-feet annually by 
2000 and 68,000 acre-feet annually by 2040, under several alternatives. Reuse is also an important 
component of the alternatives presented for the Kern Subarea. Under maximum reuse, from 6,000 
to 12,000 acres of trees and halophytes would be grown in the subarea in 2000 and 2040, 
respectively. 

The ground water hydrology of the Kern Subarea is perhaps the least understood of all the 
subareas. But, based on the available information, including some recent field work, ground 
water pumping is included for 1,500 acres in 2000 and 7,000 acres in 2040. Application of land 
retirement criteria lead to retiring 19,000 acres by 2000 and 43,000 acres by 2040. 

Significant areas of evaporation ponds are not included under any alternative. The maximum 
acreage of new ponds included in any of the alternative plans is 1,600 acres. 



113 



Figure 26 
PROBLEM WATER REDUCTION 

TULARE SUBAREA 



300 -| 


LEVEL "A" 

SOURCE CONTROL EMPHASIS 


^ 


200- 




SOURCE CONTROL 


100- 


/S^ 


REUSE 




V[^ EVAPORATION PONDS 


-^s 


- 




A , 



LEVEL -B- 

SOURCE CONTROL EMPHASIS 




1990 



GROUND WATER MANAGEMENT 



2040 1990 



GROUND WATER MANAGEMENT 



2040 



< 

o 
o 
o 



i 



-J 
O 
> 



300 



200 



100 



GROUND WATER MANAGEMENT 
EMPHASIS 




GROUND WATER 


MANAGEMENT 






EMPHASIS 








^.^^ 




r 


^ 


SOURCE CONTROL 




^^ 


^^ 


-^ 


REUSE 


^--— """IvAPORATiaN 


PONDS 


,_^ 


^^^^ 


r:^^^^^ 




1 


GROUND 


WATER 


MANAGEMENT 

'T ) 



1990 



2040 1990 



2040 



300- 


LAND RETIREMENT 
EMPHASIS 


^^ 


200- 




SOURCE CONTROL 


100- 




REUSE 




\,.,^ EVAPORATION PONDS , 

_ -t— 









■■ ^ ^ 



LAND RETIREMENT 
EMPHASIS 




1990 



G W MGT, 



2040 1990 



2040 



YEARS 



YEARS 



NOTE: Actions that reduce problem water less than 5000 acre -feet 
annually are not shown, but are discussed in the text. 



114 



Table 20. 



MAJOR FEATURES OF TULARE SUBAREA PLANNING ALTERNATIVES 

In 1,000s 



Performance 

Level and Plan 

Emphasis 


Shallow 

Ground 

Water 

Area^ 


Land 

Af- 

fected^ 


Problem 

Water 
Volume' 


Con- 
served- 
Water* 


Land Re- 
using 
Drainage' 


Land 
Re- 
tired* 


Land 
Overly- 
ing GW 
Pump- 
ing' 


Area of 
Existing 
Evapo- 
ration 
Ponds 


Area of 
New 

Evapo- 
ration 
Ponds 




Acres 


Acres 


Acre-feet 


Acre-feet 


Acres 


Acres 


Acres 


Acres 


Acres 


A-2000 




















Source Control 


359.0 


125.0 


94.0 


43.9 


11.3 


0.0 


0.4 


2.4 


0.0 


Ground Water 
Management 


359.0 


125.0 


94.0 


43.9 


7.4 


0.0 


19.3 


2.5 


0.0 


Land 
Retirement 


359.0 


125.0 


94.0 


43.9 


10.7 


0.0 


1.4 


2.4 


0.0 


A-2040 




















Source Control 


387.0 


347.0 


260.4 


156.3 


23.3 


0.0 


7.1 


2.0 


0.0 


Ground Water 
Management 


387.0 


347.0 


260.4 


132.5 


12.6 


0.0 


135.4 


2.0 


0.0 


Land 
Retirement 


387.0 


347.0 


260.4 


156.3 


23.3 


0.0 


6.7 


2.0 


0.0 


B-2000 




















Source Control 


359.0 


125.0 


94.0 


43.9 


11.3 


0.0 


0.8 


2.4 


0.0 


Ground Water 
Management 


359.0 


125.0 


94.0 


43.9 


9.5 


0.0 


8.4 


2.4 


0.0 


Land 
Retirement 


359.0 


125.0 


94.0 


43.9 


11.3 


0.0 


0.4 


2.4 


0.0 


B-2040 




















Source Control 


387.0 


347.0 


260.4 


156.3 


23.3 


0.0 


5.7 


2.5 


0.0 


Ground Water 
Management 


387.0 


347.0 


260.4 


132.5 


17.0 


0.0 


94.5 


2.5 


0.0 


Land 
Retirement 


387.0 


347.0 


260.4 


156.3 


23.3 


0.0 


5.7 


2.5 


0.0 



1 Irrigated land area with a depth to shallow ground water less than 5 feet. 

2 That portion of shallow water areas drained. 

3 The forecasted annual drainage volume that must be managed; drained land x 0.75 acre-feet per acre of deep percolation 

4 Water supply conserved by on-farm water conservation measures and management practices on problem water lands. 

5 Acreage in trees and halophyles. 

6 Lands targeted for retirement from irrigated agriculture (excluding lands designated for other uses). 

7 Land area where pumping from the semiconfmed aquifer is used to lower shallow water table below crop root zone. 



115 



Figure 27 
PROBLEM WATER REDUCTION 

KERN SUBAREA 



150 n 



100 



50- 



LEVEL "A" 



SOURCE CONTROL EMPHASIS 



LEVEL "B" 



0) 
^ 




SOURCE 


CONTROL 

EVAP. 


EMPHASIS 

PONDS - 


^52- 


SOURCE CONTROL 
REUSE 










, « , 



1990 



GROUND WATER MANAGEMENT 



2040 1990 



GROUND WATER MANAGEMENT 



2040 



O 

o 
o 



ID 

H 
< 

5 



o 

> 



IbO- 


GROUND WATER MANAGEMENT 




EMPHASIS 


100- 






^'^ SOURCE CONTROL 


50 - 


y^ ^ 




/ ^ REUSE 




^^.--''^ EVAPORATION PONDS 


-1 


1— , 1 .— ' 1 



GROUND WATER 


MANAGEMENT 






EMPHASIS 


^ 




SOURCE 


CONTROL 


/^ 


-^ 


-—— 


REUSE 


/>--''"''"^ 


EVAP. 


PONDS 






"— — ■ W 




GROUND 


VifATER 


MANAGEMENT 













1990 



GROUND WATER MANAGEMENT 



2040 1990 



2040 



150 



100 



50 



LAND 


RETIREMENT 








EMPHASIS 










/ 


/ 


/ 


^ 


^ 


SOURCE CONTROL 
REUSE 


/^- 


" 


,,- EVAPORATION 


PONDS 









■# 


^_= 




^ J , 



LAND RETIREMENT 
EMPHASIS 




1990 



YEARS 



G W MGT 2040 1990 



YEARS 



G W MGT 2040 



NOTE: Actions that reduce problem water less than 5000 acre -feet 
annually are not shown, but are discussed In the text. 



116 



Table 21. MAJOR FEATURES OF KERN SUBAREA PLANNING ALTERNATIVES 

In 1,000s 



Performance 

Level and Plan 

Emphasis 


Shallow 

Ground 

Water 

Area' 


Land 

Af- 

fected^ 


Problem 

Water 
Volume' 


Con- 
served- 
Water* 


Land Re- 
using 
Drainage^ 


Land 
Re- 
tired' 


Land 
Overly- 
ing GW 
Pump- 
ing' 


Area of 
Existing 
Evapo- 
ration 
Ponds 


Area of 
New 

Evapo- 
ration 
Ponds 




Acres 


Acres 


Acre-feet 


Acre-feet 


Acres 


Acres 


Acres 


Acres 


Acres 


A-2000 




















Source Control 


1100 


61.0 


45.8 


21.4 


6.0 


ao 


2.6 


1.3 


01 


Ground Water 


110.0 


61.0 


45.8 


21.4 


6.0 


3.2 


2.5 


1.3 


0.0 


Management 




















Land 


llOO 


61.0 


45.8 


20.2 


5.7 


3.2 


2.5 


1.2 


0.1 


Retirement 




















A-2040 




















Source Control 


167.0 


1500 


112.6 


67.5 


11.7 


oo 


6.9 


1.5 


0.0 


Ground Water 


167.0 


150.0 


112.6 


67.6 


11.2 


0.0 


6.9 


1.6 


00 


Management 




















Land 


167.0 


1500 


112.6 


66.2 


11.5 


3.1 


5.6 


1.6 


0.0 


Retirement 




















B-2000 




















Source Control 


noo 


61.0 


45.8 


21.4 


6.0 


0.0 


2.6 


1.2 


01 


Ground Water 


IIO.O 


610 


45.8 


21.4 


6.0 


0.0 


2.6 


1.3 


0.0 


Management 




















Land 


110.0 


61.0 


45.8 


14.8 


4.1 


18.7 


1.5 


1.0 


oo 


Retirement 




















B-2040 




















Source Control 


167.0 


1500 


112.6 


676 


11.2 


OO 


67 


1.6 


oo 


Ground Water 


167.0 


150.0 


112.6 


67.6 


11.2 


0.0 


6.9 


1.6 


0.0 


Management 




















Land 


167.0 


150.0 


112.6 


44.5 


8.7 


42.6 


4.8 


1.6 


0.0 


Retirement 





















1 III ig.ilcd l;irul .-nca wilh a dcplh lo shallow ground walcr loss than 5 feel. 

2 Thai portion of shallow waler areas drained. 

^ The forecasted annual drainage volume Ihal must be managed; drained land x 0.75 acre-feet per acre of deep percolation 

4 Water supply conserved by on-farm water conservation measures and management practices on problem water lands. 

5 Acreage in trees and halophytes. 

h lands targeted for retirement from irrigated agriculture (excluding lands designated for other uses). 

7 I .inc! area wliere pumping from the semiconfined aquifer is used to lower shallow water table below crop root zone. 



117 



SUMMARY AND CONCLUSIONS FROM ANALYSES OF 
SUBAREA PLANNING ALTERNATIVES 

Table 22 summarizes the major components of drainage management alternatives for the study 
area (the four subareas for which alternatives were prepared). 

The alternatives were developed to show the effects of emphasizing different strategies for 
managing drainage water. The conclusions that follow are based on analysis of the alternatives 
and are used in formulating the recommended plan presented in Chapter 6: 

• Few major differences exist among the six alternatives presented in each subarea, due 
primarily to the narrow ranges of choice actually available when physical constraints, present 
and likely environmental regulations, and costs are considered. The lack of difference is also 
due to the inclusion of source control and reuse in all alternatives. These options were 
included because they are available technologies that could be applied throughout the study 
area and because of their comparative cost advantage. 

• The opportunity for discharge of drainage water to the San Joaquin River causes the 
Grasslands Subarea to differ considerably from other subareas. 

• The planning alternatives show that the amount of water conserved by on-farm methods of 
drainage-water source control ranges from about 250,000 to 370,000 acre-feet annually by 2040. 
When land retirement and ground-water management are added to source control, the range 
of water conserved increases to 530,000 to 950,000 acre-feet annually by 2040. Water 
conserved by source control and ground-water management would benefit the water user, and 
values are taken to lower the costs of these options. It is assumed that at least 2.6 acre-feet 
per acre of water would be freed by land retirement, but no value is taken in this analysis 
because the value of the water is included in the market value of the irrigated lands to be 
purchased. 

• The analyses show how specific alternatives serve certain objectives that could be considered 
auxiliary to the objective of all plans of the Drainage Program — solving the drainage water 
problem. For example, the objective of conserving water at least cost would be served best by 
maximizing the source control and reuse options. If minimizing risk from toxicants were the 
dominant objective, then the land retirement component should be maximized. 

• A practical mix of drainage management options will not be found by formulating plans to 
adhere strictly to the criteria for performance Level A or performance Level B. However, 
analysis of alternatives formulated in that way provides a base for designing a plan that is 
more efficient than either Level A or B, or the future-without alternative. 

• Because of the complexities of the interactive factors involved in solving the drainage 
problems and the many unknowns, only limited success has been achieved in modeling the 
natural and cultural features of the problem area. This has prevented asking "what-if" 
questions that could generate an infinite number of alternatives. Professional judgment, local 
experience, and public review will evidently continue to be the most important resources in 
developing a successful plan. 



118 



Table 22. MAJOR FEATURES OF STUDY AREA PLANNING ALTERNATIVES 

in 1 ,000s 



Performance 

Level and Plan 

Emphasis 


Shallow 

Ground 

Water 

Area^ 


Land 
Af- 
fected* 


Problem 

Water 
Volume' 


Con- 
served- 
Water* 


Land Re- 
using 
Drainage' 


Land 
Re- 
tired* 


Land 
Overly- 
ing GW 
Pump- 
ing' 


Area of 
Existing 
Evapo- 
ration 
Ponds 


Area of 
New 

Evapo- 
ration 
Ponds 




Acres 


Acres 


Acre-feet 


Acre-feet 


Acres 


Acres 


Acres 


Acres 


Acres 


A-2000 




















Source Control 


857.0 


410.0 


307.4 


133.3 


29.8 


0.0 


7.1 


4.2 


0.1 


Ground Water 


857.0 


410.0 


307.4 


132.4 


20.8 


5.8 


56.9 


4.4 


0.0 


Management 




















Land 


857.0 


410.0 


307.4 


124.9 


26.9 


24.1 


7.7 


4.0 


0.1 


Retirement 




















A-2040 




















Source Control 


999.0 


898.0 


673.9 


369.9 


51.7 


0.0 


19.7 


4.1 


0.1 


Ground Water 


999.0 


898.0 


673.9 


286.3 


33.9 


0.0 


310.0 


4.2 


0.01 


Management 


















0.1 


Land 


999.0 


898.0 


673.9 


334.8 


50.1 


49.9 


17.7 


4.0 




Retirement 




















B-2000 




















Source Control 


857.0 


410.0 


307.4 


133.3 


32.1 


0.0 


8.1 


4.0 


0.1 


Ground Water 


857.0 


410.0 


307.4 


133.3 


27.1 


0.0 


34.2 


4.3 


0.0 


Management 




















Land 


857.0 


410.0 


307.4 


114.7 


27.6 


53.2 


4.8 


3.8 


0.0 


Retirement 




















B-2040 




















Source Control 


999.0 


898.0 


673.9 


369.9 


53.9 


0.0 


19.4 


4.3 


0.1 


Ground Water 


999.0 


898.0 


673.9 


310.3 


44.7 


0.0 


200.5 


4.7 


0.1 


Management 




















Land 


999.0 


898.0 


67.3 


254.5 


42.2 


219.7 


13.2 


4.1 


0.1 


Retirement 





















1 Irrigated land area with a depth to shallow ground water less than 5 feet. 

2 That portion of shallow water areas drained. 

3 The forecasted annual drainage volume that must be managed; drained land x 0.75 acre-feet per acre of deep percolation 

4 Water supply conserved by on-farm water conservation measures and management practices on problem water lands. 

5 Acreage in trees and halophytes. 

6 Lands targeted for retirement from irrigated agriculture (excluding lands designated for other uses). 

7 Land area where pumping from the semiconfined aquifer is used to lower shallow water table below crop rtwt zone. 



119 



Chapter 6. THE RECOMMENDED PLAN 



The plan presented here is intended as a regional framework for management of drainage and 
drainage-related problems on the western side of the San Joaquin Valley. It consists of a set of 
actions that are quantified to the degree possible with information currently available. Actions 
are planned to continue over the 50-year period, from 1990, through a near-term planning horizon 
(2000), and on to a long-term planning horizon (2040). Actions are quantified and described for 
the two planning horizons. 

Under the assumptions and conditions of the plan, no decision need be made now on exporting 
salt from the San Joaquin Valley. As explained in a later section of this chapter, "Rationale on 
Salt Balance," that decision can be deferred. Most, if not all, of the actions proposed in the 
recommended plan would be required as the first phase of any out-of-valley export system. 

Uncertainties in the scientific information base, plus difficulties in forecasting human events, 
necessitate that the plan be updated from time to time as monitoring, additional studies, and local 
actions reveal new facts. 

PLAN FORMULATION PROCEDURE 

The recommended plan contains some aspects of both A and B performance levels from 
alternatives presented in Chapter 5. Performance standards used in formulating the 
recommended plan are shown in Table 23. The applicability of drainage management options in 
each water quality zone was assessed by using the performance standards (Table 24). 

The sequence of plan formulation is illustrated in Figures 28, 29, and 30. The following 
discussions are provided as a guide to the decision points and places where judgment was 
applied. A detailed and comprehensive explanation of the technical processes and data used in 
formulating the plan is set forth in a report by the SJVDP (D.G. Swain, 1990). 

Land Retirement Decisions 

Land retirement was generally considered for inclusion as a plan component on lands that are 
saline and/or difficult to drain (class 4, USER classification, for example) and where shallow 
ground water contains high selenium levels (50 ppm or more). Such decisions must, however, be 
based on all factors at the site and on the other alternatives available for managing the drainage 
problem. They do not preclude the future option of re-establishing irrigated agriculture if 
circumstances should change. 

Source Control Decisions 

Measures to control subsurface drainage at the source should generally be applied to all lands 
with drainage problems, except those that may be retired from irrigated agriculture. The specific 

121 



Table 23. PERFORMANCE STANDARDS USED TO FORMULATE RECOMMENDED PLAN 



Category 


Feature 


Planning Criteria 




SAN JOAQUIN RIVER 
near NEWMAN 


BORON :< 0.7 ppm 

SELENIUM <.5 ppb 

MOLYBDENUM j^lO ppb 




SALT and MUD 
SLOUGHS 


SALINITY <.2.000 ppm TDS 

BORON <2 ppm 

SELENIUM <.2ppb 

MOLYBDENUM :^10 ppb 


WATER 

QUALITY 

(mean monthly) 


AGRICULTURAL 
WATER 
SUPPLY 


SALINITY ^L250 ppm TDS 

BORON :^1 ppm 

OR 

1,250 ppm TDS <_SALINITY :^2.500 ppm TDS 

BORON <_! ppm 

(with dilution or restricted use) 




WETLAND 
WATER SUPPLY 


SAUNITY :^L250 ppm TDS 

BORON <_! ppm 

SELENIUM <2 ppb 




REUSE OF SUBSURFACE 
DRAINAGE ON SALT- 
TOLERANT PLANTS 


EUCALYFIUS TREES ^10,000 ppm TDS 
HALOPHYTES :^25,000 ppm TDS 




EVAPORATION POND 


INFLUENT QUALITY 

SELENIUM <.2 ppb (No alternative habitat required) 

SELENIUM >2 and < 50 ppb (Alternative habitat required) 

SELENIUM ^50 ppb (No traditional evaporation ponds) 




PUMPING SEMICONFINED 
AQUIFER 


INITIAL AQUIFER THICKNESS ^200 feet 
INITIAL SALINITY < L250 ppm TDS" 


WATER 
QUANTITY 


GRASSLANDS WETLAND 

HABITAT SUBSTITUTE 

WATER SUPPLY 

WATER SUPPLY FOR 

EVAPORATION POND 

ALTERNATIVE HABITAT 


SUPPLY 129,000 acre-feet per year 

(74,000 acre-feel per year of fresh water plus facilities to provide 

at least 55,000 acre-feet of spills and tailwater) 

SUPPLY 10 acre-feet per acre per year 




SUPPLEMENTAL FISHERY FLOWS - 

MERCED RIVER near 

STEVINSON 


SUPPLY 20,000 acre-feet per year 
(provided in October) 




DESIGN LIMIT TO REGIONAL DEEP 
PERCOLATION 


LIMIT IS 0.4 acre-foot per acre per year" 


LAND 


WILDUFE HABITAT 


ALTERNATIVE HABITAT EQUAL IN SIZE TO 

EVAPORATION POND AREA WHERE 

Se INFLUENT >2 and < 50 ppb 


USE 


RHIIREMENT OF IRRIGATED 
AGRICULTURAL LANDS 


LANDS WITH >.50 ppb Se CONC. IN SHALLOW 

GROUND WATER AND RELATIVELY LOW 

PRODUCTIVITY (CLASS 4) DUE TO HIGH 

SALINITY AND POOR DRAINAGE CONDITIONS 



As salinity of pumped water exceeds 1,250 ppm TDS, its use as irrigation water becomes limited; however, it is considered usable 
for very salt-tolerant crops if salinity does not exceed 2,500 ppm TDS. 

Tliat portion of applied irrigation water passing the root zone which requires drainage management. An additional 0.1 to 0.3 ac-ft/ac/yr 
of deep percolation is assumed to move downward through the Corcoran Clay layer. 



122 



Table 24. APPLICABILITY OF DRAINAGE MANAGEMENT OPTIONS 
(Recommended Plan Performance Standards) 



Subareas 

and 

Water Quality 


Drainage 
Source 


San 
Joaquin Riv- 
er Dis- 


Salt- 
Tolerant Trees 


Halo- 
phytes 


Land Retirement' 


Existing 
Evaporation 


Nev» Evaporation 
Ponds' 


Ground 
Water Management 


Zones 




charge' 














Grasslands 


















A 


X 


Y(2lkAF) 


X 


X 


Y(3k Ac) 


Y(0 Ik Ac) 


NA(>2ppbSe) 


Y(9k Ac) 


B 


X 


Y(l5kAF) 


X 


X 


NA(<50ppbSe) 


NA 


X 


NA(2£X) ft thick) 


C 


X 


X 


NK 


NR 


NR 


NR 


NK 


NR 


D« 


X 


NR-W 


NR-W 


NR-W 


NR-W 


NR-W 


NR-W 


NR-W 


Westlands 


















A 


X 


NA 


X 


X 


Y(5K Ac.) 


NA 


NA(<2ppbSe) 


NA( > 200 ft th ick) 


B 


X 


NA 


NA( > 10k ppm TDS) 


X 


Y(15KAc,) 


Y(aik Ac) 


NA( > 2 ppb Se) 


NA(< 200 ft thick) 


C 


X 


NA 


X 


X 


Y(13K Ac) 


NA 


NA(>2ppbSe) 


Y(38k Ac) 


D 


X 


NA 


X 


X 


NA(<50ppbSe) 


Y(0.4k Ac) 


NA(>2ppbSe) 


Y(24k Ac.) 


Tulare 


















A 


X 


NA 


X 


X 


NA(<50ppbSe) 


Y(0 5k Ac) 


X 


Y(916k Ac) 


B 


X 


NA 


NA( > 10k ppm TDS) 


X 


Y(7k Ac) 


Y(3 6k Ac.) 


NA(>2ppbSe) 


NA( < 200 ft thick) 


C 


X 


NA 


X 


X 


NA(<50ppbSe) 


Y(0.2k .\c) 


NA(>2ppbSe) 


NA(< 200 ft thick) 


D 


X 


NA 


NA( > 10k ppm TDS) 


X 


NA(<50ppbSe) 


Y(a3k Ac) 


NA(>2ppbS<;) 


Y(31k Ac) 


E 


X 


NA 


X 


X 


NA(<50ppbSe) 


Y(0.3k Ac) 


X 


Y(90k Ac) 


Kern 


















A 


X 


NA 


NA( > 10k ppm TDS) 


X 


Y(24 Ac) 


Y(13k Ac) 


NA(>2ppbSe) 


NA(< 200 ft thick) 


B 


X 


NA 


NA(>10KppmTDS) 


X 


NA(<50ppbSc) 


NA 


NA(.2 ppb Sc) 


NA( < 200 ft thick) 


C 


X 


NA 


X 


X 


NA( < 50 ppb Se) 


Y(0 2k Ac) 


X 


NA(< 200 ft thick) 


D 


X 


NA 


NA(>10kppmTDS) 


X 


Y(8k Ac) 


Y(0.2k Ac) 


NA(>2ppbSe) 


NA(< 200 ft thick) 



■ Applicability of option depends on selenium criterion (mean monthly concentration of 2 ppb) and critical year hydrology (1986-87) for San Joaquin River 

near Nevvman. Selenium load expected to drop up to 50 percent by 2040 as a result of removing salts from the shallow ground water and soils. 

' A combination of >50 ppb selenium concentration in the shallow ground water and relatively low land productivity due to high soil salinity and poor drainage condi- 

tions (USBR Class 4 or equivalent SCS soil classification) was used to select lands on which imgated agnculture would be discontinued. 

' New evaporation ponds can be used when drainage water selenium concentration exceeds 2 ppb and is <50 ppb^ however, mitigation measures including alternative 

habitat must be provided. 

* Manage wildlife wetland area. 

X Option is applicable without any limitation in its application. 

Y Option IS applicable but limited to the quantities and units included in the parentheses. 

NA Option not applicable because it failed to meet the performance standard in parentheses (see Table 7) or not physically available in the instances of discharge to the 

San Joaquin River 
NR Option not suggested because increased conservation with resulting increased salinity will lower the likelihood that drainage water can be used for wetland babitat. 
NR-W Option is not applicable since shallow ground water within wetlands benefits waterfowl. 



123 



Figure 28 
OVERALL PLAN FORMULATION SEQUENCE 



Maximum Potential 
Drainage Volume 



0,6 01 075 AF,Ac. 



LAND 

RETIREMENT 



Retire Lands with 
Poor Drainage 
Characteristics 

and High Selenium 



SOURCE 
CONTROL 



DISCHARGE 



GROUND- 
WATER 
MANAGEMENT 



REUSE 



REUSE 



EVAPORATION 
SYSTEM 



NO 



I 



Reduce Volume of 
Applied Water 



NO 



^ 04 



YES 



AF/Ac. 



Discharge 
to SJ River 



NO h* 



I 



YES 



Pump 

Semiconfined 

Aquifer 



YES 



NOw^ Aquitenhickni 



ickness < 200 ft 



Irrigate 
Trees 



NO 



YES 



— TDS>10Kppm 



I 



Irrigate 
Halophytes 



NO 



YES 



TDS > 25K ppm 



£ 



Evaporate 
Drainage 



Class 4 Lands 
YES with Shallow GW > 50 ppb Se 



Reduction of 
Potential 
Drainage 

Hate- 0.60 or 0.75 AF/Ac. 



Reduction of 
Potential 
Drainage 

Rate. 0.20 Of 0.35 AF/Ac. 



Drain Flows 

Exceed 

Assimilative 

Capacity 



NO 



YES 



Drainage 
Reduction 

Rate = 0.4 AF/Ac 




Aquifer thickness 
>200 ft with < TDS 1250 ppm 



( See Figure 29 ) 



Drainage 
Reduction 

Rate = 0.4 AF/Ac. 



Salt 
iDisposal^ 



TDS< 1 0K ppm 



-^ 



Drainage 
Reduction 

Rate = 5 AF/Ac 



Drainage Return Flow =1.5 AF/Ac. 



TDS < 25K ppm 



Drainage 
Reduction 

Rate = 3 AF/Ac. 



Drainage Return Flow = t.O AF/Ac. 



( See Figure 30 ) 



Salt 
iDisposaiy 



124 



Figure 29 
PLAN FORMULATION SEQUENCE 
Pump Semiconfined Aquifer 



Pump Semiconfined 
Aquifer 



YES 



<1250ppmTDS 

>• 



NO 



— 1250ppm<TDS<2500ppm 



Water used for irrigation 

of salt- tolerant trees or 

use as solar pond cover 

layers. 



Results in some 

restriction on use as an 

irrigation supply. 



Once pumped water 

quality deteriorates to 

> 2500 ppm TDS. 



Cease pumping and 
install tile drains. 



Figure 30 

PLAN FORMULATION SEQUENCE 

Evaporate Drainage 



Evaporate Drainage 



NO - sosoppb 



YES Sc<2ppb — Ponds 



Accelerated Evaporation 
System 



I 



Solar Energy Generation 
System 



Drainage Reduction 

Rate = 4.0 AF/Ac 



J 




2 ppb < Sc < 50 ppb — Poods and Allcmativc Habitat 



Drainage Reduction 

80% Reduced Volume 




125 



source control measures adopted will vary according to the types of crops grown and individual 
grower preference. Application of source control measures could eliminate an average of nearly 
50 percent of the total problem water volume (pre-1985 conditions) by reducing deep percolation 
and, hence, potential drainage water. The rate at which source control can be implemented is 
generally controlled by the rate at which investments can be made to improve irrigation practices. 
The recommended plan takes this into account. 

In the recommended plan, source control measures were not applied to water-quality Zone C and 
a portion of Zone B in the Grasslands Subarea. These zones contain low selenium and 
moderately saline water of a quality suitable for use in wetlands or for direct discharge to the San 
Joaquin River during much of the year. 

The water collected in on-farm drains would have four possible fates: discharge to the San 
Joaquin River, water supply for wildlife areas (if selenium concentration is low), reuse on 
salt-tolerant plants, and/or discharge to evaporation ponds. 

Decisions on Discharge to the San Joaquin River 

The levels of performance required of the recommended plan in affecting the quality of water in 
the San Joaquin River were determined by State water-quality objectives and by scientific 
investigations of the U.S. Fish and Wildlife Service. It was determined that the selenium 
objectives of 5 ppb in the river and of 2 ppb in Mud and Salt sloughs were the most difficult 
objectives to be met. For planning, it was assumed that, if the selenium objective were met, then 
the boron and salt objectives could also be met. 

Accordingly, the Drainage Program focused on the assimilative capacity of the San Joaquin River. 
The plan identifies means to collect and isolate (from wetlands) a comparatively small volume of 
high-selenium water in the Grasslands Subarea. That drainage volume would then be conveyed 
through a rehabilitated and extended San Luis Drain for discharge to the San Joaquin River 
below its confluence with the Merced River. It was also decided that the plan should include 
supplementing the Merced River with fresh water obtained from the eastern side of the San 
Joaquin Valley. 

Replacement of the contaminated agricultural drainage water delivered and used in wetland areas 
before 1985 is a requirement of all plans. Mud and Salt Sloughs would not be used to convey 
water to wildlife habitat unless the selenium concentration of the supply is less than 2 ppb. 

Reuse Decisions 

It was assumed that, with some exceptions for the Grasslands Subarea, all water collected in tile 
drains would be reused on salt-tolerant trees and halophytes. This component is included in the 
plan under the conditional requirement that monitoring and analyses of the concentration of 
toxicants in biota (.selenium, for example) would be necessary to give warning of any incipient 
problem and allow for remedial measures (keeping eucalyptus groves free of forest litter, for 
example). Reuse would eliminate a significant volume of problem water. The drainage water 
from trees and halophytes would be disposed of in evaporation ponds and solar ponds. 



126 



Evaporation Pond Decisions 

The quality of drainage water (primarily selenium concentration) determines the selection, design, 
and operation of an evaporation system. It was assumed that all evaporation ponds would be 
designed and built according to criteria of the California Department of Fish and Game, which 
specify steep side slopes and minimum allowable pond depth (Bradford, et al., 1989). In addition, 
if influent selenium concentration is greater than 2 ppb, alternative, safe habitat equal to the pond 
area would be provided to facilitate hazing waterfowl from the pond area. If the influent 
concentration exceeds 50 ppb, an accelerated-rate evaporation pond would be used to reduce the 
required pond area because open ponds would not be considered feasible in the long run under 
these conditions. When possible, evaporation ponds would be located on the least productive 
agricultural land and at the lowest elevations of the drained areas. 

Treatment for Selenium Removal 

Although it is probable that an economical biological treatment process to remove selenium from 
drainage water will become available within the next 10 to 20 years, treatment is not included in 
the recommended plan. Instead, plan components are based on available technology. Treatment 
methods to remove selenium should be pursued and, when available, might replace or modify 
ground-water management or the evaporation processes. Treatment research should be continued 
not only on selenium removal but also on other toxic substances, such as arsenic, which are 
sometimes found in high concentrations in drainage water. 

Ground-Water Pumping Decisions 

Some growers now pump irrigation water from certain zones of the semiconfined aquifer. This 
pumping could be done in a more systematic and coordinated manner to focus specifically on 
lowering, and maintaining at lower levels, the shallow water table of drainage problem areas. 
Criteria for selecting potential pumping areas include adequate thicknesses of aquifers and water 
quality. Because pumping would eventually draw poor-quality water from higher in the aquifer 
into the producing wells, the length of time pumping could be continued was determined by the 
thickness of the aquifer zone and the rate of pumping. For an area to be included in the plan, the 
estimated life of the well field had to exceed 20 years. Application of planning criteria made a 
relatively minor amount of problem water area amenable to this component. 

Rationale on Salt Balance 

Implementation of the recommended plan would allow maintenance of a salt balance in the plant 
root zone. Primarily, this would be accomplished by source control and by drainage to remove 
shallow ground water and the salts it contains from crop root zones. This is in contrast to 
future-without conditions (described in Chapter 5), in which a salt balance could not be 
maintained and would lead to salinization and abandonment of lands within the next few decades 
because of problems associated with a persistently high water table. 

The main value of actions proposed in the recommended plan would be to reduce or dampen the 
present effects of the dissolution-evaporation cycle in which salts are precipitated in soils through 
evaporation of water from a near-surface water table. The present principal source of salts is not 
imported water but the high concentrations of natural salts that have been leached from soils 



127 



(particularly during the last 30 to 40 years) and are now concentrated in shallow ground water 
(CH2M Hill, 1988). These salts tend to recycle seasonally through the soil under high water table 
conditions. 

Implementation of the recommended plan would maintain the water levels below the root zone. 
The problem water would be managed by tile drains, land retirement and ground-water pumping. 
The shallow water table would be lower and thus contribute less to evapotranspiration. 

How long can such a strategy work, since about 3 million tons of salt per year are being added to 
the shallow ground-water system of the study area? The Drainage Program's answer is based on 
the assumption that the potential to continue to store salts in the subsurface (as now occurs) will 
be approaching exhaustion when subsurface water is saturated with salts in concentrations that 
exceed 2,500 ppm. When that water-quality condition is reached in the semiconfined aquifer, it is 
theorized, it will also have contributed to increased degradation of the confined aquifer (below the 
Corcoran Clay layer). Assuming that growers will not pump water of this salt content, most of the 
beneficial hydraulic stresses that moved drainage water downward will have ended. The water 
table will rise again, and it will become difficult to manage salt in crop root zones. 

As a basis for estimating the useful life of the semiconfined aquifer, available ground-water data 
were analyzed for 1.7 million acres of land, including all waterlogged areas. Analyses showed that 
about one-third of these lands already overlie portions of the semiconfined aquifer where ground 
water generally exceeds 1,250 ppm TDS. Total dissolved solids of 1,250 ppm is considered the 
maximum allowable limit for most irrigation use. For the remaining two-thirds of these lands, 
estimates were made of the rate at which saline ground water (greater than 2,500 ppm TDS) 
would displace the usable ground water by downward movement beneath the problem water 
areas. It was assumed that the flow in the semiconfined aquifer was essentially vertical and was 
governed by the rate of movement through the Corcoran Clay. 

The rate of downward movement of salts in the semiconfined aquifer was estimated at several 
locations in each of the subarea water-quality zones. The thickness of the usable aquifer and the 
rate of movement then determined the aquifer life. Aquifer life was considered to be exhausted 
when the quality of pumped ground water exceeded 2,500 ppm TDS. From the several locations 
analyzed in each subarea water-quality zone, the minimum and maximum aquifer thickness and 
life were based on one location each. The mean aquifer thickness and life were based on all 
locations analyzed. The number of locations varied from zone to zone. Table 25 shows the 
estimated useful aquifer life for water-quality zones in the Grasslands, Westlands, and Tulare 
subareas. The Northern Subarea is considered to be in salt balance, and insufficient information 
is available to estimate aquifer life in the Kern Subarea. 

Under the assumptions and conditions stated above, the western valley has several decades 
remaining before salt removal and/or export will be required. 

The process of salt contamination of ground water was set in motion decades ago with the onset 
of intense irrigation (Gilliom, et al., 1989a), and it will continue — to some extent — within the 
realm of probable use and management of water in the valley, regardless of the handling of the 
regional drainage problems. If it were possible to balance salt inflow and outflow in the valley, 
this would help slow the rate of salt contamination of ground water. 



128 



Table 25. ESTIMATED USEFUL LIFE OF THE SEMICONFINED AQUIFER 





Percent of Wa- 


Present Thickness and Remaining Life of Semlconflned Aquifer 


Subarea 


Mean 


Minimum 


Maximum 


Water 


ter Quality 


Thickness" Llfe<= 


Thickness" Life'= 


Thickness" 


Life'= 


Quality 


Zone Area with 


(feet) (years) 


(feet) (years) 


(feet) 


(years) 


Zone 


Usable Ground 
Water» 










Grasslands 
















A 


35 


50 


75 


350 


525 


160 


250 


B 


79 


50 


25 


200 


100 


130 


65 


C 


66 


50 


150 


150 


450 


90 


270 


Westlands 
















A 


33 


50 


35 


200 


190 


150 


110 


B 


64 


50 


30 


350 


210 


180 


110 


C 


70 


50 


30 


450 


270 


190 


115 


D 


781 


50 


25 


400 


200 


220 


110 


Tulare 
















A 


19 


50 


75 


250 


375 


125 


185 


D 


100 


50 


25 


500 


250 


330 


165 


E 


88 


50 


25 


450 


225 


335 


170 



a Usable ground water contains less than 1250 ppm TDS. 

b Thickness refers to that part of the semiconfined aquifer containing usable ground water. 

c Life of the aquifer is the estimated time for saline ground water (greater than 2,500 ppm TDS) to completely displace presently 
usable ground water, in the semiconfined aquifer. It is calculated by dividing the aquifer thickness of usable ground water by 
the average rate of water movement across the Corcoran Clay. It was assumed that pumping from the confined aquifer be- 
neath the Corcoran Clay will be maintained at current rates. 



Management of drainage problems in the manner presented in the recommended plan tends to 
enhance near-term (up to 50 years) protection of soils and off-site impacts of drainage discharges, 
while continuing to diminish the life (for direct irrigation) of westside aquifers. 

A functionally beneficial aspect of the recommended plan is that it includes the preliminary steps 
that would likely be needed when salt removal from the valley becomes necessary and feasible. 
These steps include integrated in-valley systems to collect and reduce the volume of drainage 
water, accompanied by containment and control of contaminants, such as selenium. 

PLAN FEATURES COMMON TO ALL SUBAREAS 

Several plan features are common to all subareas. The following discussion is intended to reduce 
the need for repetitive description of the recommended subarea plans. 

The features that are an essential part of the plans for all subareas (exclusive of the Northern 
Subarea) are: drainage-water source control, reduction of drainage-water volume by reuse, 
disposal of concentrated drainage-water, changes in water institutions, and monitoring of the 
drainage-water environment. 

Drainage-Water Source Control 

Improvement in the application of irrigation water to reduce the source of deep percolation has 
been shown to be the most effective and least costly means of reducing the amount of potential 



129 



drainage problem water. Recognizing the necessity to leach salts past the root zone and the 
nonuniformity of soils, even in a single agricultural field, there is justifiable argument about the 
amount of improvement that can be achieved in irrigation water application to reduce deep 
percolation. Field demonstrations show, however, that irrigation water application can be 
improved (Boyle, 1990, 1989a, 1989b). Target reductions in deep percolation believed attainable 
through on-farm water conservation measures by 2000 and sustainable beyond that time are 
shown, by subarea, in Table 26. The comparatively low target for the Tulare Subarea reflects the 
average higher efficiencies in water application that prevail in that subarea now. 

Table 26. RECOMMENDED TARGETS FOR 
REDUCTION IN DEEP PERCOLATION IN 2000 



Subarea Target Reduction 

(acre-feet/acre) 

Northern 0.0" 

Grasslands 0.35 

Westlands 0.35 

Tulare 0.20 

Kern 0.35 



° See discussion for Northern Subarea under "Description and 
Evaluation of Recommended Plan (by Subarea)" later in this chapter. 



The target deep percolation reductions in Table 26 are included as part of the recommended plan 
for all irrigated lands in each subarea. 

Reducing deep percolation on lands lying upslope (up the hydraulic gradient) from drainage 
problem areas would benefit downslope areas. The results of geologic investigations (Quinn, 
1990) suggest that, over decades, the aquifers above the Corcoran Clay function as a set of 
regional aquifers. Therefore, water conservation on upslope areas is important, even though the 
impact on a downslope problem water area will probably not be nearly as immediate and direct 
as will water conservation practiced directly on downslope lands with drainage problems. Even 
on upslope lands, which are significantly larger in total area than downslope lands, a moderate 
level of water conservation could have a significant effect on the waterlogging problems — in the 
long run. 

An exception to the universal inclusion of source control in the recommended plan is in the 
Northern Subarea and parts of the Grasslands Subarea lying in the basin trough. In these areas, 
source control is not included because of the relatively low levels of selenium occurring in the 
shallow ground water and the composition of the dissolved salts that are low in gypsum 
(W.C. Swain, 1990c). Program analyses (D.G. Swain, 1990) indicate that application of source 
control in these areas would not contribute to meeting present State water quality objectives nor 
appreciably reduce the salt load in the San Joaquin River — assuming that the present policy 
agreement requiring releases from New Melones Reservoir remains in effect to dilute the salt load 
in the San Joaquin River. 



130 



Reduction of Drainage-Water Volume by Reuse 

The large volume of drainage water that is generated annually^ (from 0.60 to 0.75 foot per acre in 
the water-quality zones) presents a difficult but not insurmountable problem for in-valley 
management. Assuming that source control measures would eliminate from 0.2 to 0.35 acre-foot 
per acre, the balance of 0.40 acre-foot per acre would have to be collected and reduced in the 
most economic means available, while meeting acceptable levels of environmental protection. 

The first essential collection device in reuse is on-farm tile drains. Presently, there are only 
133,000 acres of installed drains in all the westside area. The Drainage Program projects that the 
area drained by on-farm systems will increase to about 760,000 acres by 2040 (Table 27). 

Table 27. PROJECTED ON-FARM TILE DRAINAGE ACREAGE 

(Acres) 

SUBAREA 1990 2000 2040 



Northern 


24,000 


34,000 


44,000 


Grasslands 


50.000 


108,000 


192.000 


Westlands 


5,000 


69,000 


140,000 


Tulare 


43,000 


96,000 


277,000 


Kern 


11,000 


53,000 


106,000 


TOTAL 


133,000 


360,000 


759,000 



Subsurface water collected in the farm drains would be transported to the primary water 
reduction facility used in the recommended plan: salt-tolerant tree plantations and fields of 
halophytes. These plants would be irrigated with enough drainage water to leach salts from the 
root zone and meet the maximum capacity of the given species to transpire water. Transpiration 
is about 5 acre-feet per acre per year for eucalyptus trees and 3 acre-feet per acre per year for 
halophytes. Drainage from the trees and halophytes would average about 1.5 acre-feet per acre 
per year for a total application rate of 6.5 and 4.5 acre-feet per acre per year, respectively. An 
acre of trees would serve an average of about 16 acres of drained cropland. The trees would be 
located as close to the drained farmlands as possible.^ The tree plantations would require 
subsurface drains, not only to remove salts from the root zone but also to provide feed water for 
the fields of halophytes. which would be located near the trees. In some parts of the Westlands, 
Tulare, and Kern subareas, drainage water would be too salty to use on trees and, therefore, 
halophytes would be the primary drainage reduction mechanism. 

The acreages of trees and halophytes required for the recommended plan are given in Table 28. 
The atypical decline in acreages in the Grasslands Subarea is explained in the Grasslands plan 
later in this chapter. 



If on-farm drains were available, the estimated volume in 1990 would be about 300,000 acre-feet per year. Based 
on analyses of water table measurements for 1977, 1983, and 1986-87, this volume is forecasted to more than 
double from 1990 to 2040. 

In addition to proximity to drained croplands, important land suitability criteria for the reduction facilities are: 
elevation, soils that can be drained, the absence of soil characteristics adverse to the species selected, and soils not 
suited for high-value crops. 



131 



Table 28. PRIMARY DRAINAGE-WATER REDUCTION FACILITIES 

(Approximate acres) 



2000 



2040 



Subarea 


Trees 


Halophytes 


Trees 


Halophytes 


Grasslands 


2,400 


900 


1.9(K) 


700 


Westlands 


3,900 


2,100 


8,000 


4,100 


Tulare 


4,000 


4,600 


12„300 


12,300 


Kern 


1,600 


3,300 


3,600 


6.000 


TOTAL 


11,900 


10,900 


25,800 


23,100 



Disposal of Concentrated Drainage Water 

Other than in the Grasslands Subarea, the primary means of disposal of the residual drainage 
water and dissolved solids it contains would occur in evaporation and solar pond facilities. These 
pond systems would bear little resemblance, in structure or operation, to present evaporation 
ponds. A number of features would be changed to improve their safety and efficiency. 

In the staged design of the recommended plan, ponds would follow drainage-water-volume 
reduction and, consequently, less pond area would be required than would be under current 
conditions. Compared to present pond acreages, the total acreage of ponds in 2040 would be 
about half the present, and each unit of pond area would serve about 8 to 10 times as much 
drained land as do ponds in 1990. 

The estimated life of an evaporation pond is 30 years. Old ponds would be closed safely, and new 
ponds would replace them. The pond area in 2040, by type, in each subarea, is given in Table 43. 

Institutional Components 

The recommended plan contains several institutional components that are included in all 
subareas: tiered water pricing, improved scheduling of irrigation deliveries, water marketing, and 
formation of regional drainage management organizations. These are either new to the subarea or 
have never been applied at the scale that would be needed to implement this plan. 

Tiered Water Pricing 

Tiered water pricing means increasing irrigation water rates as more water is applied. This would 
provide incentives for water conservation. Although water districts are not allowed to make 
profits, water revenue surpluses could be used to help finance on-farm water conservation 
measures. Tiered water pricing is already being implemented by three water districts in the 
Grasslands Subarea. 

Improved Scheduling of Water Deliveries 

The aim of improved scheduling of water deliveries is to enable growers to obtain irrigation water 
deliveries when their land and crops need the water, not when the delivering entity can supply the 
water. In all the subarea plans, costs have been included, under the category of source control, to 
effect considerable improvements in scheduling water deliveries. These changes would build on 
the present programs of the California Department of Water Resources and several local water 
districts. 



132 



Water Transfers and Marketing 

This would provide incentives for water conservation, wherein local water districts and/or 
irrigators would be permitted to retain some portion of the increase in the value of water sold for 
a profit. The portion of the increase in value retained by the suppliers in a transfer would also 
help fund water conservation measures. The Department of Water Resources and the Bureau of 
Reclamation are the principal agencies that could develop and implement policies and programs 
for water transfers and marketing. 

Some transfers would require the approval of the State Water Resources Control Board. All 
transfers of State Water Project and Central Valley Project water would require, respectively, the 
authorization of the Department and the Bureau as project operator. Tliomas and 
Leighton-Schwartz (1990) declare there are no serious legal impediments to the transfer of water 
made available by reclamation or conservation from drainage problem areas in the western San 
Joaquin Valley. Purpose and place of use restrictions in the CVP permits and contracts may be 
amended to facilitate transfers of project water to other uses or areas. The increases in 
repayment obligations in moving water from irrigation to municipal and industrial use do not 
appear to be substantial disincentives, according to Thomas. 

Regional Drainage Management Organizations 

Regional drainage management organizations are recommended for the Grasslands and Tulare 
subareas, with all upslope and downslope areas to be included within the boundaries of the 
organization. Such organizations would coordinate the drainage-related operations of existing 
local water entities, with respect to activities and issues that transcend local entity boundaries. 
Local water entities are in the best position to effectively manage the subsurface drainage 
problem because they deal with water throughout the hydrologic cycle in a given land area. 
Generally, they have the authority to manage drainage water; where they do not, the authority 
could be obtained through legislation. However, in recognition of hydrologic and economic 
linkages and relationships among local water entities, some drainage problems could probably be 
managed best at a regional level. For such needs, either regional entities or joint-power 
authorities could be formed. 

A regional drainage management organization could reduce drainage management costs, bring 
about coordination among several local entities, and help internalize the costs of drainage 
management. 

Westlands Water District could serve as the regional drainage management entity for the 
Westlands Subarea. In the Kern Subarea, Kern County Water Agency, through joint-powers 
agreement with the water districts or some other organizational arrangement, could serve as the 
regional drainage management entity. 

Monitoring of the Drainage-Water Environment 

The drainage problem that affects, or is related to, more than 1 million acres is not presently 
being monitored in a comprehensive, effective, and efficient manner. An extremely important 
premise underlying successful implementation of this plan is that the many facets and dimensions 
of the problem — ground-water levels, soil conditions, land uses, water quality, volume of 
drainage, conditions of evaporation ponds, impacts on biota, public health risks — must be 
monitored on a long-term, systematic basis. The objective of monitoring is to determine the effect 

133 



of actions and whether they should be changed. In 1990, no one can forecast with certainty what 
conditions will be in 2040. The strategy presented in this plan will, no doubt, have to be adjusted 
in response to unforeseen human events and responses of natural systems. 

DESCRIPTION AND EVALUATION OF THE RECOMMENDED PLAN 

Northern Subarea 

No actions are recommended as part of a regional plan for the Northern Subarea (Figure 31). 
This is based on two assumptions: (1) State water-quality regulations for the San Joaquin River 
will continue to allow salt discharge to the river from ground-water seepage and from surface and 
subsurface drainage water originating from irrigation in the Northern Subarea, and (2) fresh water 
will continue to be released from New Melones Reservoir to help meet State water-quality 
objectives at the Vernalis gaging station. 

It was stated earlier in this report that both a water balance and a salt balance have nearly been 
achieved under existing hydrologic conditions in this subarea. As long as drainage water and 
seepage can be discharged to the San Joaquin River under the assumptions stated above, then no 
actions beyond those in place now would be required. However, if more restrictive objectives are 
adopted for either boron or salt in the river, this balance would have to be interrupted to reduce 
drainage water and salt and boron load. 

In the event of possible new water-quality restrictions, the following two measures would aid in 
reducing drainage discharge to the river. Source control measures to reduce deep percolation on 
about 50,000 acres of irrigated land with water tables less than 5 feet from the surface would 
reduce drainage water inflow to the river; however, they would also increase concentrations of salt 
in the remaining subsurface drainage water. (For estimates and calculations, see AWMS, 1987, 
and D. G. Swain, 1990). Increased pumping of deep ground water to replace some of the surface 
water currently being used for irrigation would lower the high water table and reduce both 
drainage volume and seepage of salty ground water to the river. 

A measure that should be studied further in relation to more restrictive water-quality objectives in 
the San Joaquin River is pumping shallow ground water into the river during high flows to create 
underground storage space for percolating agricultural drainage water. If feasible, this would 
improve river water quality by storing salty drainage water during low river flow. There are 
technical problems that may be insurmountable in terms of storage space and the short periods of 
time during which the flows could be accepted in the river (D.G. Swain, 1990). A variation of 
this option would be to intercept shallow, salty ground water moving to the river and pump it into 
surface-water storage ponds used as wildlife habitat. A possible drawback to this measure is that 
the average concentration of selenium in the intercepted moderately deep ground water may 
exceed the selenium water-quality objectives in the river (5 ppb). The ponds could be drained to 
the river during high flows and refilled during low-flow periods. 



134 



Figure 31 

NORTHERN SUBAREA 




LEGEND 
Subarea Boundary 



N 

I 



LOCATION MAP 



SCALE IN MILES 




Grasslands Subarea 

Figure 32 shows the shallow ground-water quality zones. Agricultural components of the 
recommended plan for the subarea are listed in Table 29. Selected facilities and flows are shown 
on Figure 33. 

The agricultural components of the recommended plan for 2040 are: 

• Practicing source control on 93,600 acres of irrigated land. The amount of water 
applied to irrigate drainage problem areas would be reduced, on the average, by 

0.35 acre-foot per acre per year (a total of 32,700 acre-feet) by improving methods of 
irrigation water application, by improving scheduling of irrigation water application, 
and by tiered water pricing. 

• Reusing drainage water to irrigate 2,600 acres of salt-tolerant trees and 
halophytes. Through installation of on-farm tile drains and conveyance facilities, 
drainage water would be collected and supplied to trees to reduce the total drainage 
volume by 10,900 acre-feet. Drains would be installed beneath the trees to collect the 
brackish water drained for subsequent use by halophytes. This would reduce the 
drainage volume by another 2,700 acre-feet, for a total reduction of 13,600 acre-feet. 
These reuse plantations could serve individual farms or an entire water or drainage 
district and would be located on the least productive soils. Most sites would be 
located on Storie Index class 4, 5, or 6 soils on the Panoche and Little Panoche Creek 
fan rim in the eastern part of water-quality Zone A. 

• Operating 120 acres of evaporation ponds and 130 acres of solar ponds. Pond 
design and operation criteria would be consistent with State guidelines, and ponds 
would be located near tree and halophyte plantations. The volume of influent water 
evaporated annually would be about 700 acre-feet. 

• Pumping the semiconfined aquifer under about 10,000 acres of land. Due to 

natural features, this option is most feasible in the southeastern and northwestern 
portions of the subarea. The design average annual yield would be 0.4 acre-foot per 
acre of land affected, for a total management of 4,000 acre-feet of problem water. To 
exert this effect at the land surface, 8,000 acre-feet would have to be pumped from the 
aquifer. These lands would also have received source control (0.35 acre-foot per acre), 
but they would not be artificially drained. Pumped ground water of initial good quality 
could be used for agriculture, or fish and wildlife, or a variety of other uses. If, in 
future years, influent water to a well should contain dissolved salt in excess of 
2,500 ppm TDS, that water would be used for trees and halophytes. or as top water in 
solar ponds. This component would be applicable only in water-quality Zones A and B. 

• Retiring 3,000 acres of irrigated agricultural lands. Lands having the combined 
characteristics of poor drainability, high salinity levels, and high levels of dissolved 
selenium (greater than 50 ppb) in shallow ground water would be retired. Only lands 
in water-quality Zone A met this criterion. 



136 



w. 



Figure 32 

GRASSLANDS SUBAREA 
Ground-Water Quality Zones 



^\<^ 




LEGEND 
Subarea Boundary 
A I Ground Water Quality Zone 



N 

I 



LOCATION MAP 




Table 29. RECOMMENDED DRAINAGE MANAGEMENT PLAN 
GRASSLANDS SUBAREA (In 1000s) 





YEAR 2000 


YEAR 2040 


PLAN 
COMPONENT 


AR^AL 
APPLICATION 

OF 
COMPONENT 


PROBLEM WATER 
REDUCTION 


AREAL 
APPLICATION 

OF 
COMPONENT 


PROBLEM WATER 
REDUCTION 




Acres 


AF 


% 


Acres 


AF 


% 


ZONE A 














SOURCE CONTROL 


68.9 


24.0 


44.4 


72.0 


25.1 


44.3 


LAND RETIREMENT 


0.0 


0.0 


0.0 


3.0 


2.3 


4.0 


GROUND-WATER MGMT 


5.0 


2.0 


3.7 


10.0 


4.0 


7.1 


DRAINAGE REUSE' 


3.1 


16.5 


30.6 


0.8 


4.1 


7.2 


EVAPORATION SYSTEM 


0.18 


0.8 


1.5 


0.12 


0.2 


0.4 


DISCHARGE TO SJ RIVER 


26.8 


10.7 


19.8 


525 


21.0 


37.0 


Total 




54.0 


100.0 




56.7 


100.0 


ZONEB 














SOURCE CONTROL 


6.8 


2.4 


22.8 


21.6 


7.6 


21.6 


LAND RETIREMENT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


GROUND- WATER MGMT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE 


0.4 


1.1 


10.0 


1.8 


9.5 


27.0 


EVAPORATION SYSTEM 


0.01 


0.1 


0.6 


0.12 


0.5 


1.4 


DISCHARGE TO SJ RIVER 


9.3 


7.0 


66.6 


23.5 


17.6 


50.0 


AND OR WETLANDS 














Total 




10.6 


100.0 




35.2 


100.0 


ZONEC 














SOURCE CONTROL 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


LAND RETIREMENT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


GROUND-WATER MGM T 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE' 


0.0 


0.0 


0.0 


0.0 


00 


0.0 


EVAPORATION SYSTEM 


0.0 


0.0 


0.0 


0.00 


0.0 


0.0 


DISCHARGE TO SJ RIVER 


29.3 


22.0 


100.0 


84.7 


63.5 


100.0 


AND OR WETLANDS 














Total 




22.0 


100.0 




63.5 


100.0 


TOTAL 














SOURCE CONTROL 


75.7 


26.4 


30.5 


93.6 


32.7 


21.0 


LAND RETIREMENT 


0.0 


0.0 


0.0 


3.0 


2.3 


1.4 


GROUND-WATER MGMT 


5.0 


2.0 


2.3 


10.0 


4.0 


2.6 


DRAINAGE REUSE" 


3.5 


17.6 


20.3 


2.6 


13.6 


8.8 


EVAPORATION SYSTEM 


0.2 


0.9 


1.0 


0.2 


0.7 


0.5 


DISCHARGE TO SJ RIVER 


65.4 


39.7 


45.9 


160.6 


102. 1" 


65.7 


AND OR WETLANDS 














Total 




86.6 


100.0 




155.4 


lOO.O 



Includes potential drainage from irrigated agricultural land used to grow salt tolerant crops. 

Increases in volume from year 2000 to year 2040 are due largely to improvements forecasted to occur over time in the quality of 
shallow ground water drained from irrigated lands. For data and interpretation supporting this concept, see Gilliom, et al., (1989a) 
and Deverel and Gallathine (1988). 



138 



• Discharging about 1 02,000 acre-feet of drainage water^ to wetlands and/or the 
San Joaquin River (while meeting river water-quality standards). About 
63,500 acre-feet of subsurface drainage water of adequate quality^ for fish and wildlife 
uses would be discharged from water-quality Zone C into Salt Slough, from which 
diversions could be made to adjacent public and private wetland management areas. 
About 17,500 acre-feet of subsurface drainage water from west of the wetland area 
(water-quality Zone B) would also be of adequate quality for use in wetland habitat 
areas. About 21,000 acre-feet of subsurface drainage water from irrigated land 
(water-quality Zone A) south of the Grasslands wetland area would be unsuitable for 
reuse in wetlands and, therefore, would be discharged into the San Luis Drain for 
delivery to the San Joaquin River below its confluence with the Merced River. The 
sediments removed from the drain would be placed within the Kesterson Reservoir 
disposal area and treated as the Kesterson sediments were managed in that cleanup 
effort. The amount of drainage water discharged is limited by the river criteria near 
Newman (Table 7). The San Luis Drain would be cleaned of sediments and modified 
structurally to receive drainage from water quality Zone A at a point near South Dos 
Palos, and the drain would be extended to the San Joaquin River, below the confluence 
of the Merced River. The Main, Panoche, Hamburg, and Charleston drains would be 
interconnected and routed to the San Luis Drain near South Dos Palos. The San Luis 
Drain thus would become the means by which a portion of the contaminated 
subsurface drainage now entering the South Grasslands area would be re-routed 
around the wetlands. 

Management of agricultural drainage problems and protection, restoration, and substitute water 
supplies for fish and wildlife are planned as complementary activities. The interception of 
contaminated subsurface drainage water currently discharged into waterways of the Grasslands 
wetland area would make available nontoxic tailwater, operational spills, and nontoxic subsurface 
drainage for use in the wetlands. 

Plan components for protection, restoration, and substitute water supplies for fish and wildlife in 
the Grasslands Subarea are shown on Figure 33 and discussed in the following subsections. 

• Providing, on a firm basis, 129,000 acre-feet per year of adequate-quality water from 
existing sloughs, ditches, and canals that serve the Grasslands area. This volume is 
the average amount of surface and subsurface drainage water diverted to the wetlands 
before 1985, when use of the contaminated drainage water for wetland management 
was discontinued. It is assumed that the quantity and quality of tailwater, operational 
spills, and local runoff will continue to be suitable for fish and wildlife water supplies 
throughout the period of the plan. The 129,000 acre-feet of water could be obtained 
by: 



^ Assumption used to calculate the volume of drainage water discharged: (a) Dry-year hydrology similar to the 1986-87 
water year, (b) existing 150 ppb selenium in subsurface drainage water, decreased to 75 ppm by 2040. and (c) 5 ppb 
selenium criteria in the San Joaquin River near Newman. 

" TDS less than 1,250 ppm, boron less than 1 ppm, and selenium less than 2 ppb. 



139 



Figure 33 

FACILITIES AND FLOWS INCLUDED IN THE RECOMMENDED PLAN 

Grasslands Subarea 




C 



Notes 



/^ Notes I 



LEGEND 
Agricultural Facility 



Water Supply for Wetlands 
or Supplement to River 



N 



LOCATION MAP 



SCALE IN MILES 




SJVDP 



— Providing up to about 74,000 acre-feet from the Central Valley Project through the 
Delta-Mendota Canal for diversion into wetland areas. 

— Delivering an average of 45,000 acre-feet of tailwater, operational spills, and local 
runoff of adequate quality from water-quality Zone C to Salt Slough for use in 
wetlands. 

— Delivering up to 10,000 acre-feet of tailwater, operational spills, and local runoff 
from water-quality Zone B to Los Banos Creek and vicinity. 

• Providing the facilities necessary to deliver 74,000 acre-feet of substitute water, 
including a Delta-Mendota Canal Turnout with a capacity of 200 cubic feet per second 
and 1.75 miles of 200-cfs canal and siphons, to the wetlands of South Grasslands. 

• Providing facilities to intercept all subsurface drainage water now being discharged 
from water-quality zone A into open channels in the Grasslands; facilities would also 
be provided to convey this water to the San Luis Drain near South Dos Palos. 

• Using an estimated 63,500 acre-feet of subsurface drainage water from water-quality 
Zone C, and 17,500 acre-feet of subsurface drainage water from Zone B, by 2040, in 
wetlands. Most of this water would flow by gravity to Salt and Mud sloughs, where it 
would be conveyed to public and private wetlands. 

• Providing, on a firm basis, an additional 20,000 acre-feet of fresh water to supplement 
October flows in the Merced River. This would minimize the straying of migrating 
adult salmon into the Grasslands instead of into the natural spawning grounds in the 
Merced River. This water must be obtained by purchasing surface or ground water 
from water-rights holders in the Merced River drainage or by extending the northern 
end of the Friant-Madera Canal into the Merced River watershed so that water stored 
behind Friant Dam could be delivered to the Merced River. Purchasing water in the 
Merced River drainage appears to be the most economical approach. 

• Providing alternative wetland habitat near evaporation ponds. Because the selenium 
concentrations in the evaporation ponds would exceed 2 ppb, a hazing program would 
be required to discourage bird use. In addition, wetland habitat (one acre for each 
acre of evaporation ponds) would be developed close to the evaporation ponds to offer 
alternative clean habitat for hazed birds. Each acre of alternative habitat would 
require about 10 acre-feet of water per year. 

Assessment of Plan Features and Their Effects 

The plan for the Grasslands Subarea relies on the continued discharge of subsurface drainage 
water to the San Joaquin River, either directly to the river or through sloughs and wetlands. The 
opportunity for the discharge of contaminated subsurface drainage water depends on the flows in 
the San Joaquin River, the concentrations of contaminants in the subsurface drainage water, and 
the limiting water-quality objective at the point of discharge. Interception of contaminated 
subsurface drainage water south of the Grasslands Subarea and delivery to the San Luis Drain 
near South Dos Palos for conveyance to the San Joaquin River below the Merced River are key 
features of the plan. The removal and disposal of sediments within the San Luis Drain are 
necessary conditions for use of the drain as a plan component. 



141 



About half the subsurface drainage water would be suitable as a fish and wildlife water supply. 
Under conditions of the recommended plan, the quality of water delivered to the wetlands would 
be the best-quality water delivered since subsurface drainage was first introduced to the marsh 
area, and the volume (more than 129,000 acre-feet) would approximate the optimal water 
requirement for wildlife habitat in the subarea. Construction of the proposed wetland 
water-supply intertie facilities would provide the flexibility needed to ensure that the water would 
be delivered on an optimal schedule, assuming sufficient water is available in the Delta and 
sufficient capacity in the Delta-Mendota Canal to deliver the substitute water. 

Table 30 compares the recommended plan features with those of the present and projected 
future-without conditions. The recommended plan would keep about 36,000 more acres of 
existing irrigated agricultural lands in production than under future-without conditions. 

The annualized costs of the components of the recommended plan for the Grasslands Subarea are 
presented in Table 31. The category "Agricultural Drainage" comprises all drainage-related 
components of the recommended plan, except on-farm drainage systems. "On-Farm Drains" 

Table 30. COMPARISON OF PLAN WITH PRESENT AND FUTURE-WITHOUT CONDITIONS, 

GRASSLANDS SUBAREA 
In 1,000s 





Present 
(1990) 


Future- 


Recommended 


Item 


without 


Plan 




(2040) 


(2040) 


Agricultural Land Area (acres) 








Irrigable agricultural Land 


365 


303 


339 


Drainage reuse 





2 


3 


Abandoned and/or retired agricultural land 





40 


3 


Evajxjration System 








Nontoxic evaporation pond 


0.00 


0.00 


0.00 


Toxic evaporation pond 


0.10 


0.20 


012 


Accelerated evaporation pond 


0.00 


0.00 


0.02 


Solar pond 


OOO 


0.00 


0.13 


Evaporation pond alternative habitat 


OOO 


OOO 


0.12 


Urban expansion 


C 


20 


20 


TOTAL ^ 


365 


365 


365 


Wildlife Areas (acres) " 








Wetlands 


68.0 


24.0 


55.0 


Other 


29.0 


72.4 


41.4 


Abandoned wildlife areas 


ao 


06 


06 


TOTAL 


97.0 


97.0 


97.0 


Water Freed in Addressing Drainage Problems 





122' 


55" 


(acre-feet) 








Firm Water Supply for Wildlife Areas (acre-feet) 


97 


97 


226 


Water Supply for Evaporation Pond Alternative 








1 


Habitat (acre-feet) 









Evaporation systems are located on existing pond sites or on retired or nonirrigable lands, so are not included in "Total." 
Federal and State wildlife areas, private duck clubs, and other private wildlife areas. 

Includes increased conserved water through source control on problem water lands and firm water supply freed by land 
abandonment and conversion of crop land to salt-tolerant crops. 

Includes increased conserved water through source control on problem water lands; firm water supply freed by land re- 
tirement and conversion of cropland to salt-tolerant crops; and ground water pumped to control water levels within prob- 
lem water areas. 



142 



includes the installation of new on-farm drainage systems from 1991 to 2040 and the annual 
operation from 1991 to 2040 of the newly installed drains and those already operating in 1990. 
"Fish and Wildlife" comprises the costs of constructing and operating facilities and purchasing 
water to deliver clean replacement water to waterfowl habitat formerly supplied with 
contaminated drainage water. 

One-time costs include those for installation of facilities and purchase of land retired from 
irrigated agriculture. Costs were annualized, using an interest rate of 10 percent to reflect 
opportunities available to growers and a 50-year planning period. The grand total cost for the 
Grasslands Subarea would amount to about $107 per acre of problem farmland served by 
components of the recommended plan. This includes the cost of the fish and wildlife 
components. If these costs were separated, the per-acre cost to farmland served would be $81. 

Included in the total cost is a provision necessary to minimize the risks to wildlife from 
evaporation ponds. The ponds in which the selenium level exceeded 2 ppb (the level assumed to 
be safe for wildlife) would include special features, such as steep side slopes, increased depth, 
hazing, and alternative habitat. 

Table 31. ANNUALIZED COSTS OF THE RECOMMENDED PLAN FOR THE GRASSLANDS SUBAREA 



AGRICULTURAL DRAINAGE 








One-time: 








Source control 

Reuse 

Evaporation 

Ground-water management 

Land retirement 

San Luis Drain 




$ 622,000 

845,000 

224,000 

193,000 

55,000 

2.300.000 




Subtotal 




$4,239,000 




Operation, maintenance, and reolacement 








Source control 

Reuse 

Evaporation 

Ground-water management 

Land retirement 

San Luis Drain 




$1,232,000 
145,000 
239.000 
549,000 
6,000 
390.000 




Subtotal 




$2,561,000 






Total 




$ 6,800,000 


ON-FARM DRAINS 








Installation 




$2,653,000 




Operation, maintenance, and replacement 




584.000 






Total 




$ 3,237,000 


FISH AND WILDLIFE 








Installation 

Operation, maintenance, and replacement 

Water supply 


Total 


$ 153.000 

18,000 

2.548.000 


$ 2,719,000 




GRAND TOTAL 




li2js>m. 



143 



Westlands Subarea 

Figure 34 shows the location of the ground-water quality zones within the subarea. Agricultural 
components of the recommended plan for the subarea are shown on Table 32. 

The agricultural components of the recommended plan for 2040 are: 

• Practicing source control on 159,300 acres of irrigated land. The amount of 
applied irrigation water would be reduced by 0.35 acre-foot per acre per year (a total 
of 55,800 acre-feet) by improving methods of irrigation water application, improving 
scheduling of irrigation water application, and tiered water pricing. 

• Reusing drainage water to irrigate about 12,100 acres of salt-tolerant trees and 
halophytes. Through installation of on-farm tile drains and conveyance facilities, 
drainage water would be collected and supplied to trees to reduce the total drainage 
volume by 45,700 acre-feet. Drains would be installed beneath the trees to collect the 
brackish water for direct use by halophytes. This would reduce the drainage volume 
by another 15,300 acre-feet, for a total reduction of about 61,000 acre-feet. These 
reuse plantations could serve individual farms or an entire water or drainage district. 
They would be located on the least productive soils, with most sites on class 4 soils on 
the alluvial fan rims. These soils occur in the eastern part of the subarea near the San 
Luis Drain. Existing collector drains and the San Luis Drain would be used to convey 
drainage water to reuse plantations. 

• Operating 400 acres of evaporation ponds and about 1 ,500 acres of solar 
ponds. Pond design and operation criteria would be consistent with State guidelines, 
and the ponds would be located close to tree and halophyte plantations. About 

200 acres of additional land would be used for accelerated-rate evaporation facilities. 

• Pumping the semiconfined aquifer under about 19,000 acres of land. Due to 

natural features, this option is most feasible in the southeastern portion of the 
subarea. The design average annual yield would be 0.4 acre-foot per acre of land 
affected, for a total management of 7,600 acre-feet of problem water. To exert this 
effect at the land surface, 16,000 acre-feet would have to be pumped from the aquifer. 
These lands would also have received source control (0.35 acre-foot per acre), but they 
would not be artificially drained. Pumped ground water of initial good quality (some 
16,000 acre-feet) could be used for agriculture, or fish and wildlife, or a variety of 
other uses. If, in future years, influent water to a well should contain dissolved salt in 
excess of 2,500 ppm, that water would be used as a supply for trees and halophytes, or 
as top water in solar ponds. 

• Retiring 33,000 acres of irrigated agricultural lands. Lands having the combined 
characteristics of low productivity, poor drainability (USER class 4 lands), and high 
levels of dissolved selenium (greater than 50 ppb) in shallow ground water would be 
retired. A part of water-quality Zones A, B, and C would be retired. 



144 



Figure 34 

WESTLANDS SUBAREA 
. ^ Ground-Water Quality Zones 




A 



LEGEND 
Subarea Boundary 
Ground Water Quality Zone 



N 



LOCATION MAP 



SCALE IN MILES 




Table 32. RECOMMENDED DRAINAGE MANAGEMENT PLAN 

WESTLANDS SUBAREA 

(in 1000s) 





YEAR 2000 


YEAR 2040 


PLAN 
COMPONENT 


AREAL 
APPLICATION 

OF 
COMPONENT 


PROBLEM WATER 
REDUCTION 


AREAL 
APPLICATION 

OF 
COMPONENT 


PROBLEM WATER 
REDUCTION 




Acres 


AF 


% 


Acres 


AF 


% 


ZONE A 














SOURCE CONTROL 


11.2 


3.9 


30.2 


25.3 


8.9 


36.6 


LAND RETIREMENT 


5.0 


3.8 


29.4 


5.0 


3.8 


15.4 


GROUND- WATER MGM'T 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE" 


1.0 


4.9 


38.1 


2.2 


11.1 


45.5 


EVAPORATION SYSTEM 


0.06 


0.3 


2.3 


0.27 


0.6 


2.5 


Total 




12.9 


100.0 




24.4 


100.0 


ZONEB 














SOURCE CONTROL 


12.3 


4.3 


28.0 


21.7 


7.6 


26.3 


LAND RETIREMENT 


7.0 


5.3 


34.1 


15.0 


11.2 


38.8 


GROUND- WATER MGM'T 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE" 


1.2 


5.0 


32.7 


2.0 


8.8 


30.4 


EVAPORATION SYSTEM 


0.07 


0.8 


5.2 


0.94 


1.3 


4.5 


Total 




15.4 


100.0 




28.89 


100.0 


ZONEC 














SOURCE CONTROL 


44.4 


15.5 


38.9 


81.8 


28.6 


37.9 


LAND RETIREMENT 


6.0 


4.5 


11.3 


13.0 


9.8 


12.9 


GROUND-WATER MGMT 


10.0 


4.0 


10.0 


11.0 


4.4 


5.8 


DRAINAGE REUSE" 


2.7 


15.1 


37.8 


6.0 


31.2 


41.3 


EVAPORATION SYSTEM 


0.18 


0.8 


2.0 


0.78 


1.6 


2.1 


Total 




39.9 


100.0 




75.6 


100.0 


ZONED 














SOURCE CONTROL 


16.2 


5.7 


44.0 


30.5 


10.7 


44.0 


LAND RETIREMENT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


GROUND-WATER MGMT 


5.0 


2.0 


15.4 


8.0 


3.2 


13.2 


DRAINAGE REUSE" 


LO 


5.0 


38.3 


1.9 


9.9 


40.7 


EVAPORATION SYSTEM 


0.06 


0.3 


2.3 


0.13 


0.5 


1.3 


Total 




13.0 


100.0 




24.3 


100.0 


TOTAL 














SOURCE CONTROL 


84.1 


29.4 


36.3 


159.3 


55.8 


36.4 


LAND RETIREMENT 


18.0 


13.6 


16.7 


33.0 


24.8 


16.1 


GROUND-WATER MGMT 


15.0 


6.0 


7.4 


19.0 


7.6 


5.0 


DRAINAGE REUSE" 


5.9 


30.0 


36.9 


12.1 


61.0 


39.9 


EVAPORATION SYSTEM 


0.4 


2.2 


2.7 


1.0 


4.0 


2.6 


Total 




81.2 


100.0 




153.2 


100.0 



" Includes drainage from irrigated agricultural land used to grow salt tolerant crops. 



146 



Assessment of Plan Features and Their Effects 

Table 33 compares the recommended plan features with those of present and projected future 
conditions without a plan. Compared to future-without conditions, the recommended plan would 
maintain about 100,000 more acres of existing irrigated agricultural lands in production. By 2040, 
the plan would result in the conservation or development of 181,000 acre-feet of water through 
implementation of plan components (such as source control, conversion of land to reuse drainage 
water, land retirement, and ground-water pumping) on drainage problem areas. 

Table 33. COMPARISON OF PLAN WITH PRESENT AND FUTURE-WITHOUT CONDITIONS 

WESTLANDS SUBAREA 
In 1,000s 





Present 


Future- 


Recommended 


Item 


without 


Plan 




(1990) 


(2040) 


(2040) 


Agricultural Land Area (acres) 








Irrigable agricultural land 


640 


489 


590 


Drainage reuse 





6 


12 


Abandoned and/or retired agricultural land 





140 


33 


Evaporation System 








Nontoxic evaporation pond 


0.00 


0.00 


0.00 


Toxic evaporation pond 


0.50 


O20 


0.40 


Accelerated evaporation pond 


0.00 


0.00 


O20 


Solar pond 


0.00 


0.00 


1.52 


Evaporation pond alternative habitat 


0.00 


aoo 


O40 


Urban expansion 





5 


5 


TOTAL * 


640 


640 


640 


Wildlife Areas (acres) " 








Wetlands 


0.1 


0.1 


01 


Other 


0.4 


0.4 


0.4 


Abandoned wildlife areas 


OO 


0.0 


0.0 


TOTAL 


0.5 


0.5 


0.5 


Water Freed In Addressing Drainage Problems 





390' 


189" 


(acre-feet) 








Firm Water Supply for Wildlife Areas (acre-feet) 











Water Supply for Evaporation Pond Alternative 








4 


Habitat (acre-feet) 









Evaporation systems are located on existing pond sites or on retired or nonirrigable lands, so are not included in "Total." 
Federal and State wildlife areas, private duck clubs, and other private wildlife areas. 

Includes increased conserved water through source control on problem water lands and firm water supply freed by land 
abandonment and conversion of crop land to salt-tolerant crops. 

Includes increased conserved water through source control on problem water lands; firm water supply freed by land retire- 
ment and conversion of cropland to salt-tolerant crops; and ground water pumped to control water levels within problem 
water areas. 



The annualized costs of the components of the recommended plan for the Westlands Subarea are 
presented in Table 34. The category "Agricultural Drainage" comprises all drainage-related 
components of the recommended plan, except on-farm drainage systems. "On-Farm Drains" 
includes the installation of new on-farm drainage systems from 1991 to 2040 and the annual 
operation from 1991 to 2040 of the newly installed drains and those already operating in 1990. 



147 



One-time costs include those for installation of facilities and purchase of land retired from 
irrigated agriculture. Costs were annualized, using an interest rate of 10 percent to reflect 
opportunities available to growers and a 50-year planning period. 

The grand total cost for the Westlands Subarea amounts to about $136 per acre of problem 
farmland served through the components stipulated in the recommended plan. 

Included in the cost is a provision necessary to minimize the risk to wildlife from evaporation 
ponds. The ponds in which the influent selenium level exceeded 2 ppb (the level assumed to be 
safe for wildlife) would include special features, such as steep side slopes, increased depth, hazing, 
and alternative habitat. 



Table 34. ANNUALIZED COSTS OF THE RECOMMENDED PLAN 
FOR THE WESTLANDS SUBAREA 



AGRICULTURAL DRAINAGE 

One-time : 



Source control 


$ 829,000 




Reuse 


1,801,000 




Evaporation 


702.000 




Ground-water management 


319,000 




Land retirement 


1.930.000 




Subtotal 


$5,581,000 




Operation, maintenance, and replacement: 






Source control 


$1,588,000 




Reuse 


626,000 




Evaporation 


596,000 




Ground-water management 


903,000 




Land retirement 


208.000 




Subtotal 


$3,921,000 




Total 




$ 9,502,000 


ON-FARM DRAINS 






Installation 


$3,008,000 




Operation, maintenance, and replacement 


355.000 




Total 




$ 3,363,000 


GRAND TOTAL 




$12,865,000 



148 



Tulare Subarea 

Figure 35 shows the location of the ground-water quality zones within the subarea. Agricultural 
components of the recommended plan for the subarea are listed in Table 35. 

The agricultural components of the recommended plan for 2040 are: 

• Practicing source control on 316,700 acres of irrigated land. The amount of 
applied irrigation water will be reduced by 0.20 acre-foot per acre per year (a total of 
63,200 acre-feet) by improving methods of irrigation water application, improving 
scheduling of irrigation water application, and tiered water pricing. 

• Reusing drainage water to irrigate 24,500 acres of salt-tolerant trees and 
halophytes. Through installation of on-farm tile drains, drainage water would be 
collected and supplied to trees to reduce the total drainage volume by 68,900 acre-feet. 
Drains would be installed beneath the trees to collect the brackish water for direct use 
by halophytes. This would reduce the drainage volume by another 44,400 acre-feet, for a 
total reduction of 113,300 acre-feet. These reuse plantations could serve individual farms 
or an entire water or drainage district. They would be located on the least productive 
soils, with most sites on class 4, 5, and 6 soils (Storie Index) on the basin rim. 

• Operating 3,000 acres of evaporation ponds.^ Pond design and operation criteria 
would be consistent with State guidelines, and the ponds would be located close to tree 
and halophyte plantations. 

• Pumping the semiconfined aquifer under about 40,000 acres of land. Due to 

natural features, this option is most feasible in the northern part of water-quality 
Zones D and E. The design average annual yield would be 0.4 acre-foot per acre of land 
affected, for a total management of 16,000 acre-feet of problem water. To exert this 
effect at the land surface, 32,000 acre-feet would have to be pumped from the aquifer. 
These lands would also have received source control (0.20 acre-foot per acre), but they 
would not be artificially drained. Pumped ground water of initial good quality could be 
used for agriculture, or fish and wildlife, or a variety of other uses. If, in future years, 
influent water to a well should contain dissolved salt in excess of 2,500 ppm, that water 
would be used for trees and halophytes. 

• Retiring 7,000 acres of irrigated agricultural lands. Lands having the combined 
characteristics of low productivity, poor drainability (Storie Index 4, 5, and 6 lands), and 
overlying high selenium (greater than 50 ppb) in shallow ground water would be retired. 
All the lands lie within water-quality Zone B. 



^ No solar ponds are included because salinity levels would probably be too low to support them. 



149 



Figure 35 

TULARE SUBAREA 
Ground-Water Quality Zones/ ^ 




Avenal 



kttleman City 



J 33 



B 



jjjyj^^g_]_TULAR6^£2,_ 
KERN CO 



(411 



LEGEND 



\ 



■ Subarea Boundary 

I A I Ground Water Quality Zone 



N 



43 



LOCATION MAP 



SCALE IN MILES 




Table 35. RECOMMENDED DRAINAGE MANAGEMENT PLAN 

TULARE SUBAREA 

(in 1000s) 





YEAR 2000 


YEAR 2040 


PLAN 
COMPONENT 


AREAL 
APPLICATION 

OF 
COMPONENT 


PROBLEM WATER 
REDUCTION 


AREAL 
APPLICATION 

OF 
COMPONENT 


PROBLEM WATER 
REDUCTION 


Acres 


AF 


% 


Acres 


AF 


% 


ZONE A 














SOURCE CONTROL 


60.9 


12.2 


30.8 


169.5 


33.9 


30.8 


LAND RETIREMENT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


GROUND-WATER MGMT 


2.0 


0.8 


2.0 


3.0 


1.2 


1.1 


DRAINAGE REUSE 


5.0 


25.2 


63.7 


14.0 


7L3 


64.7 


EVAPORATION SYSTEM 


0.34 


1.4 


3.5 


0.96 


3.8 


3.4 


Total 




39.6 


100.0 




110.2 


100.0 


ZONEB 














SOURCE CONTROL 


25.0 


5.0 


30.3 


63.2 


12.6 


27.4 


LAND RETIREMENT 


0.0 


0.0 


0.0 


7.0 


4.2 


9.2 


GROUND-WATER MGMT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE 


2.5 


9.0 


54.5 


6.3 


22.8 


49.7 


EVAPORATION SYSTEM 


0.62 


2.5 


15.2 


1.58 


6.3 


13.7 


Total 




16.5 


100.0 




45.9 


100.0 


ZONEC 














SOURCE CONTROL 


1.5 


0.3 


27.3 


4.1 


0.8 


29.6 


LAND RETIREMENT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


GROUND-WATER MGMT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE 


0.2 


0.6 


54.5 


0.4 


L5 


55.6 


EVAPORATION SYSTEM 


0.04 


0.2 


18.2 


0.10 


0.4 


14.8 


Total 




LI 


100.0 




2.7 


100.0 


ZONED 














SOURCE CONTROL 


6.9 


1.4 


3L1 


19.7 


3.9 


31.4 


LAND RETIREMENT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


GROUND-WATER MGM'l 


2.0 


0.8 


17.8 


10.0 


4.0 


32.3 


DRAINAGE REUSE 


0.5 


1.8 


40.0 


LO 


3.5 


28.2 


EVAPORATION SYSTEM 


0.12 


0.5 


11.1 


0.24 


1.0 


8.1 


Total 




4.5 


100.0 




12.4 


100.0 


ZONEE 














SOURCE CON IROL 


22.1 


4.4 


32,6 


60.2 


12.0 


31.8 


LAND RETIREMENT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


GROUND-WATER MGMT 


16.0 


6.4 


47.4 


27.0 


10.8 


28.6 


DRAINAGE REUSE 


0.5 


2.6 


19.3 


2.8 


14.2 


37.5 


EVAPORATION SYSTEM 


0.04 


0.1 


0.7 


0.15 


0.8 


2.1 


Total 




13.5 


100.0 




37.8 


100.0 


TOTAL 

SOURCE CONTROL 


116.4 


23.3 


31.0 


316.7 


63.2 


30.2 


LAND RETIREMENT 


0.0 


0.0 


0.0 


7.0 


4.2 


2.0 


GROUND- WATER MGMT 


20.0 


8.0 


10.6 


40.0 


16.0 


7.7 


DRAINAGE REUSE 


8.7 


39.2 


52.1 


24.5 


113.3 


54.2 


EVAPORATION SYSTEM 


1.2 


4.7 


6.3 


3.0 


12.3 


5.9 


Total 




75.2 


100.0 




209.0 


100.0 



151 



Assessment of Plan Features and Their Effects 

Table 36 compares the plan features with those of present and projected future conditions without 
the plan. Compared to future-without conditions, the recommended plan would maintain 166,000 
more acres of existing irrigated agricultural lands in production. By 2040, the plan would result in 
the conservation or development of about 164,000 acre-feet of water through implementation of 
plan components (such as source control, conversion of land to reuse of drainage water, land 
retirement, and ground-water pumping) on drainage problem areas. 

The annualized costs of the components of the recommended plan for the Tulare Subarea are 
presented in Table 37. The category "Agricultural Drainage" comprises all drainage-related 
components of the recommended plan, except on-farm drainage systems. "On-Farm Drains" 
includes the installation of new on-farm drainage systems from 1991 to 2040 and the annual 
operation from 1991 to 2040 of the newly installed drains and those already operating in 1990. 

One-time costs include those for installation of facilities and purchase of land retired from 
irrigated agriculture. Costs were annualized, using an interest rate of 10 percent to reflect 
opportunities available to growers and a 50-year planning period. 

Table 36. COMPARISON OF PLAN WITH PRESENT AND FUTURE-WITHOUT CONDITIONS 

TULARE SUBAREA 
In 1,000s 





Present 


Future- 


Recommended 


Item 


Without 


Plan 




(1990) 


(2040) 


(2040) 


Agricultural Land Area (acres) 








Irrigable agricultural land 


612 


406 


572 


Drainage Reuse 





11 


25 


Abandoned and/or retired agiicultural land 





190 


7 


Evaporation system 








Nontoxic evaporation pond 


0.80 


0.50 


0.20 


Toxic evaporation pond 


4.10 


0.90 


2.90 


Accelerated Evaporation pond 


0.00 


0.00 


0.00 


Solar pond 


0.00 


0.00 


0.00 


Evaporation pond alternative habitat 


0.00 


0.00 


2.90 


Urban expansion 





5 


5 


TOTAL" 


612 


612 


612 


Wildlife Areas (acres)" 








Wetlands 


1.7 


0.0 


0.0 


Other 


7.7 


9.3 


9.3 


Abandoned wildlife areas 


0.0 


0.1 


0.1 


TOTAL 


9.4 


9.4 


9.4 


Water Freed in Addressing Drainage Problems 





454' 


164"* 


(acre-feet) 








Firm Water Supply for Wildlife Areas (acre-feet) 











Water Supply for Evaporation Pond Alternative 








29 


Habitat (acre-feet) 









Evaporation systems are located on existing pond sites or on retired or nonirrigable lands, so are not included in "Tbtal." 
Federal and Slate wildlife areas, private duck clubs, and other private wildlife areas. 

Includes increased conserved water through source control on problem water lands and firm water supply freed by land 
abandonment and conversion of crop land to salt-tolerant crops. 

Includes increased conserved water through source control on problem water lands; firm water supply freed by land retire- 
ment and conversion of cropland to salt-tolerant crops; and ground water pumped to control water levels within problem 
water areas. 



152 



Table 37. ANNUALIZED COSTS OF THE RECOMMENDED PLAN 



FOR THE TULARE SUBAREA 



AGRICULTURAL DRAINAGE 

One-time : 



Source control 

Reuse 

Evaporation 

Ground-water management 

Land retirement 

Subtotal 

Operation, maintenance, and replacement : 



$1,312,000 

3,111,000 

396,000 

513.000 

112.000 

$5,444,000 



Source control 

Reuse 

Evaporation 

Ground-water management 

Land retirement 


$2,450,000 

992,000 

241,000 

1,441,000 

112.000 




Subtotal 

Total 


$5,135,000 


$10,579,000 


ON-FARM DRAINS 






Installation 

Operation, maintenance, and replacement 


$3,144,000 
5?9,00O 




Total 




$ 3.733.000 


GRAND TOTAL 




$14,312,000 



The grand total cost for the Tulare Subarea amounts to about $104 per acre of problem farmland 
served through components included in the recommended plan. 

Included in the cost is a provision necessary to minimize the risk to wildlife from evaporation 
ponds. The ponds in which the influent selenium level exceeded 2 ppb (the level assumed to be 
safe for wildlife) would include special features, such as steep side slopes, increased depth, hazing, 
and alternative habitat. 

Kern Subarea 

Figure 36 shows the location of the ground-water quality zones within the subarea. Agricultural 
components of the recommended plan for the subarea are shown on Table 38. 

The agricultural components of the recommended plan for 2040 are: 

• Practicing source control on 105,900 acres of irrigated land. The amount of 
applied irrigation water will be reduced by 0.35 acre-foot per acre per year (a total of 
37,100 acre-feet) by improving methods of irrigation water application, improving 
scheduling of irrigation water application, and tiered water pricing. 



153 




Figure 36 

KERN SUBAREA 
Ground-Water Quality Zones 



KI NGS CO : TULAR E CO. 
KERN CO 



I Devils Den 



B 



1461 



. Blackwells 
Comer 



c 



Lost Hills ^ 



^, 



\ 



^i 



KERN CO 



SAN LUIS OBISPO CO. 



158 > 



iMcKiltrick 




Suttonwillow 



Bakersfield 



.^^^ 



=(11 9f 




niaft 



D 



99 



LEGEND 
Subarea Boundary 
A I Ground Water Quality Zone 



N 



LOCATION MAP 



SCALE IN MILES 




Table 38. RECOMMENDED DRAINAGE MANAGEMENT PLAN 

KERN SUBAREA 

(in 1000s) 





YEAR 2000 


YEAR 2040 










AREAL 






PLAN 
COMPONENTS 


AREAL 
APPLICATION 

OF 
COMPONENT 


PROBLEM WATER 
REDUCTION 


APPLICATION 

OF 
COMPONENT 


PROBLEM WATER 
REDUCTION 




Acres 


AF 


% 


Acres 


AF 


% 


ZONE A 














SOURCE CONTROL 


7.5 


2.6 


32.5 


LI 


0.4 


2.1 


LAND RETIREMENT 


2.2 


1.7 


21.2 


24.0 


18.0 


95.4 


GROUND- WATER MGMT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE 


0.8 


2.9 


36.3 


0.1 


0.4 


2.0 


EVAPORATION SYSTEM 


0.15 


0.8 


10.0 


0.08 


0.1 


0.5 


Total 




8.0 


100.0 




18.9 


100.0 


ZONEB 














SOURCE CONTROL 


7.8 


2.7 


42.2 


18.8 


6.6 


42.6 


LAND RETIREMENT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


GROUND- WATER MGMT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE 


0.8 


2.9 


45.3 


1.9 


7.0 


45.3 


EVAPORATION SYSTEM 


0.19 


0.8 


12.5 


0.47 


1.9 


12.1 


Total 




6.4 


100.0 




15.5 


100.0 


ZONEC 














SOURCE CONTROL 


13.4 


4.7 


43.1 


32.4 


11.3 


43.1 


LAND RETIREMENT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


GROUND- WATER MGMT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE 


1.1 


5.9 


54.2 


2.7 


14.2 


54.2 


EVAPORATION SYSTEM 


0.08 


0.3 


2.7 


0.19 


0.7 


2.7 


Total 




10.9 


100.0 




26.2 


100.0 


ZONED 














SOURCE CON IROL 


24.4 


8.5 


41.0 


53.6 


18.8 


37.5 


LAND RETIREMENT 


0.9 


0.7 


3.4 


8.0 


6.0 


12.0 


GROUND- WATER MGMT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE 


2.3 


10.0 


48.4 


5.0 


22,0 


43.9 


EVAPORATION SYSTEM 


0.34 


1.5 


7.2 


1.57 


3.3 


6.6 


Total 




20.7 


100.0 




50.1 


100.0 


TOTAL 














SOURCE CONTROL 


53.1 


18.5 


40.2 


105.9 


37.1 


33.5 


LAND RETIREMENT 


3.1 


2.4 


5.1 


32.0 


24.0 


21.7 


GROUND- WATER MGMT 


0.0 


0.0 


0.0 


0.0 


0.0 


0.0 


DRAINAGE REUSE 


5.0 


21.7 


47.3 


9.7 


43.6 


39.4 


EVAPORATION SYSTEM 


0.8 


3.4 


7.4 


2.3 


6.0 


5.4 


Total 




46.0 


100.0 




110.7 


100.0 



155 



• Reusing drainage water to irrigate 9,700 acres of salt-tolerant trees and 
halophytes. TlirDugh installation of on-farm tile drains, drainage water will be 
collected and supplied to trees to reduce the total drainage volume by 20,900 acre-feet. 
Drains would be installed beneath the trees to supply the water to halophytes. This 
would reduce the drainage volume by another 22,700 acre-feet, for a total reduction of 
43,600 acre-feet. These reuse plantations could serve individual farms or an entire 
water or drainage district. They would be located on the least productive soils, with 
most sites on class 5 and 6 soils (Storie Index) on the alluvial fans in water-quality 
Zones A and D. 

• Operating 1 ,1 GO acres of evaporation ponds and 1 ,1 GO acres of solar ponds. 

Pond design and operation criteria would be consistent with State guidelines, and the 
ponds would be located close to tree and halophyte plantations. An additional 
100 acres of land would be required for accelerated-rate evaporation systems. 

• Retiring 32,000 acres of irrigated agricultural lands. Lands having the combined 
characteristics of low productivity, poor drainability (Storie Index 4, 5, and 6 lands), 
and overlying high selenium (greater than 50 ppb) in shallow ground water would be 
retired. These lands lie within water-quahty Zones A and D. 

Assessment of Plan Features and Their Effects 

Table 39 compares the plan features with those of present and projected future conditions 
without the plan. Compared to future-without conditions, the recommended plan would maintain 
about 52,000 more acres of existing irrigated agricultural lands in production. By 2040, the plan 
would create an opportunity to free at least 753,600 acre-feet of irrigation water for other uses. 

The annualized costs of the components of the recommended plan for the Kern Subarea are 
presented in Table 40. The category "Agricultural Drainage" comprises all drainage-related 
components of the recommended plan, except on-farm drainage systems. "On-Farm Drains" 
includes the installation of new on-farm drainage systems from 1991 to 2040 and the annual 
operation from 1991 to 2040 of the newly installed drains and those already operating in 1990. 

One-time costs include those for installation of facilities and purchase of land retired from 
irrigated agriculture. Costs were annualized, using an interest rate of 10 percent to reflect 
opportunities available to growers and a 50-year planning period. 

The grand total cost for the Kern Subarea amounts to about $137 per acre of problem farmland 
served through the components stipulated in the recommended plan. 

Included in the cost is a provision necessary to minimize the risk to wildlife from evaporation 
ponds. The ponds in which the influent selenium level exceeded 2 ppb (the level assumed to be 
safe for wildlife) would include special features, such as steep side slopes, increased depth, hazing, 
and alternative habitat. 



156 



Table 39. COMPARISON OF PLAN WITH PRESENT AND FUTURE-WITHOUT CONDITIONS 

KERN SUBAREA 
In 1,000s 



Item 


Present 


Future- 


Recommended 




(1990) 


Without (2040) 


Plan (2040) 


Agricultural Land Area (acres) 








Irrigable agricultural land 


762 


632 


684 


Drainage Reuse 





5 


10 


Abandoned and/or retired agricultural land 





90 


32 


Evaporation system 








Nontoxic evaporation pond 


0.00 


0.00 


0.00 


Toxic evaporation pond 


1.70 


0.70 


1.07 


Accelerated Evaporation pond 


0.00 


0.00 


0.14 


Solar pond 


0.00 


0.00 


1.10 


Evaporation pond alternative habitat 


0.00 


0.00 


1.07 


Urban expansion 





35 


35 


TOTAL* 


762 


762 


762 


Wildlife Areas (acres)" 








Wetlands 


6.1 


0.0 


0.0 


Other 


10.9 


13.6 


13.6 


Abandoned wildlife areas 


0.0 


3.4 


3.4 


TOTAL 


17.0 


17.0 


17.0 


Water Freed in Addressing Drainage Problems (ac-ft) 





268' 


154'^ 


Firm Water Supply for Wildlife Areas (acre-feet) 











Water Supply for Evaporation Pond Alternative 








11 


Habitat (acre-feet) 









Evaporation systems are located on existing pond sites or on retired or nonirrigable lands, so are not included in "Tbtal." 
Federal and State wildlife areas, private duck clubs, and other private wildlife areas. 

Includes increased conserved water through source control on problem water lands and firm water supply freed by land 
abandonment and conversion of crop land to salt-tolerant crops. 

Includes increased conserved water through source control on problem water lands; firm water supply freed by land retire- 
ment and conversion of cropland to salt-tolerant crops; and ground water pumped to control water levels in problem water areas. 



Table 40. ANNUALIZED COSTS OF THE RECOMMENDED PLAN FOR THE KERN SUBAREA 



AGRICULTURAL DRAINAGE 

One-time : 

Source control 

Reuse 

Evaporation 

Land retirement 

Subtotal 
Operation, maintenance, and replacement : 

Source control 

Reuse 

Evaporation 

Land retirement 

Subtotal 

ON-FARM DRAINS 

Installation 

Operation, maintenance, and replacement 





$ 551,000 






1,391,000 






542,000 






652,000 






$3,136,000 






$1,051,000 






637,000 






489.000 






68.000 






$2,245,000 




Total 


$2,051,000 
288.000 


$5,381,000 


Total 




$2,339,000 


GRAND TOTAL 




$7,720,000 



157 



Evaluation of Plan and Comparison to Future-Without 

The actions included in the recommended plan for each subarea would reduce the amount of 
irrigation water used on the lands overlying problem water. The volume would be reduced 
through: (1) Water conserved through source control measures, (2) water not applied to retired 
land, and (3) water not applied to lands being supplied through reuse of drainage water (for 
example, eucalyptus trees replacing a cotton field). In addition, a relatively small volume of water, 
some 56,000 acre-feet per year, would be pumped from the semiconfined aquifer. 

The estimated water potentially available through recommended plan actions to reduce irrigation 
water application is given in Table 41. Although the water is potentially available with the plan, 
the water may not be physically available for any given use. That is because of restrictions due to 
water law (including contracts), economics, or private property rights (for example, pumped 
ground water). In the Westlands Subarea, for instance, 189,000 acre-feet annually would be 
conserved or developed in implementing the recommended plan. However, there is currently a 
shortage of irrigation water for some lands in the Westlands Water District. Consequently, water 
made available by reduced demand in the drainage problem area would probably be transferred 
to the area of shortage. Considerations of service area boundaries, priority of rights, availability 
of funds, and the full array of alternative uses for such water should be examined in more detail. 

The water needs for fish and wildlife are shown in Table 42. Comparison of Tables 41 and 42 
shows that a possible source of the water needed for fish and wildlife to offset the effects of 
drainage could be found in the water made available under the plan. It is assumed that 189,000 
acre-feet of water freed in the Grasslands Subarea may be used to satisfy the 158,000-acre-foot 
shortage in the current firm water supply of the Grassland Water District. Additional 
investigation is required to determine the means of making the needed water available. The 
investigation should include consideration of marketing part of the available water to help pay for 
costs of solving drainage problems, including protecting fish and wildlife. 



Table 41. WATER POTENTIALLY AVAILABLE THROUGH RECOMMENDED PLAN ACTIONS 




In 1,000 acre-feet annually 




Source Control 
and Reuse 


Ground-Water 
Management 


Land Retirement 


Total Water 
Available 


Subarea 


2000 


2040 


2000 


2040 


2000 


2040 


2000 


2040 


Northern 














Grasslands 


35 39 


4 8 


8 


39 55 


Westlands 


45 87 


12 16 


47 86 


104 189 


Tulare 


42 117 


16 32 


15 


58 164 


Kern 


32 64 





9 90 


41 154 


TOTAL 


154 307 


32 56 


56 199 


242 562 



Table 43 shows the area of wetlands, evaporation ponds, and solar ponds included in the 
recommended plan. The new year-round wetlands have been created to provide alternative 
habitat to unsafe evaporation ponds, and they are necessary for successful hazing. The wetlands 
would require fresh water at the rate of about 10 acre-feet per acre per year. 

Comparison of the recommended plan to the future-without conditions provides a scale for 
further evaluation of the recommended plan. Selected features of the two courses of action are 



158 



displayed in Tables 44 and 45. Table 44 shows that the recommended plan, which emphasizes 
more planned regional control of drainage water (beginning with intensive drainage water source 
control measures), provides water that could be made available for other uses, including fish and 
wildlife. However, by far the largest volume of water would be made available under 
future-without conditions, in which 1,140,000 acre-feet of water annually would not be used on 
460,000 acres of presently irrigated lands because of salinization and abandonment of those lands. 



Table 42. SUMMARY OF ANNUAL WATER NEEDS FOR FISH PROTECTION, SUBSTITUTE 
WATER SUPPLY FOR WILDLIFE AREAS, AND ALTERNATIVE HABITAT FOR EVAPORATION PONDS 

(As Related to Drainage Problem) 
In acre-feet 



Subarea 



2000 



2040 



Grasslands'' 
Westlands'' 
Tulare" 
Kern" 



TOTAL 



149,300 

2,300 

11,200 

4,600 

167,400 



150.200 

4,000 

29,000 

10,700 

193,900 



Includes 20,000 acre-feet per year for Merced River fisheries, 129,000 acre-feet per year for substitute 
water supply, and 300 acre-feet per year (2000) / 1,200 acre-feet per year (2040) for alternative habitat 
for evaporation ponds. Some substitute water supply needs can be met with existing water-district spills 
and tailwater of adequate quality (about 55,000 acre-feet per year is estimated under the recommended 
plan on a firm basis). 



" All needs are for alternative habitat to evaporation ponds. 



Table 43. AREA OF EVAPORATION AND SOLAR PONDS AND WETLANDS 

IN THE RECOMMENDED PLAN 

In acres 





Evaporation Ponds 


Solar Ponds' 








Nontoxic Ponds 


Standard 


Accelerated 
Rate Ponds* 


New Year- 




(<2 ppb 
selenium) 


Ponds (2-50 
ppb selenium) 






Round 
Wetlands" 


Subarea 


2000 


2040 


2000 


2040 


2000 


2040 


2000 


2040 


2000 


2040 


Noilhem 




















Grasslands 





10 120 


70 





110 


10 120 


Westlands 





230 410 


20 200 


140 


1,520 


230 410 


Tulare 


40 200 


1,120 2,900 











1,120 2,900 


Kern 





460 1,070 


120 140 


190 


1,100 


460 1,070 


TOTAL 


40 200 


1,820 4,500 


140 410 


330 


2,730 


1,820 4,500 



These ponds must be evaluated to determine their effect on wildlife and shallow ground water. 

Provided as alternative habitat to standard evaporation ponds (new wetlands require 10 acre-feet per acre per year). 



159 



Future-Without 


Recommended 


Conditions 


Plan 


97,000 


271,000^ 





20,000 


1,140,000 








195,000 





56,000 


54,000" 


308,000' 



Table 44. COMPARISON OF SELECTED WATER FEATURES AND EFFECTS 
OF THE RECOMMENDED PLAN AND FUTURE-WITHOUT CONDITIONS, 2040 

In acre-feet 



Water supplied to wetland areas 

Supplementation of Merced River 

Water made available by land abandonment 

Water made available through land retirement 

Water pumped from the semiconfined aquifer 

Water conserved through source control and reuse of drainage water 

a Includes, approximately: 97,000 acre-feet per year of existing firm supply; 129.000 acre-feet per year of substitute water 
supply: and 45,000 acre-feet of water to create a wetland habitat that is an alternative to toxic evaporation ponds. 

^ Conservation rate of 0.2 acre-foot per acre of drained land. 

' Conservation rate of 0.35 acre-foot per acre of drained land (except TUIare, which is 0.20 acre-foot); includes freeing of irrigation 
water supply supplanted by using drainage water on salt-tolerant plants. 



Table 45. COMPARISON OF SELECTED LAND FEATURES AND EFFECTS 
OF THE RECOMMENDED PLAN AND FUTURE-WITHOUT CONDITIONS, 2040 

In acres 



Seasonal and permanent wetlands 

Reuse areas (salt-tolerant plants) 

Irrigated land area 

Crop land drained " 

Land abandoned ' 

Land retired from irrigation 

" Does not include new wetlands created as alternative habitat for evaporation ponds because such lands are an adjunct 

of the drainage management system, not lands dedicated to wetlands. 
*■ Does not include tile drains that would be installed under salt-tolerant plants. 
' Salinization of foimcrly irrigated lands. 

Estimates of the economic benefits of fish and wildlife resources in the San Joaquin Valley have 
been based on both market (user) and nonmarket (nonuser) values (Loomis et al., 1990). The 
combined annual market and nonmarket values of fish and wildlife for the recommended plan 
exceed those values associated with the future-without alternative by a ratio of almost 2 to 1. 

Conditions that are expected to prevail with the recommended plan have been analyzed for 2040, 
and the agriculturally related economic impacts of plan conditions and future-without conditions 
for 2040 are compared in Table 46. The recommended plan would maintain more land in 
agricultural production and higher levels of retail sales, employment, and income. About 
360,000 more acres would be kept in irrigated agriculture, with an associated crop value of 
$285 million. The positive impact on retail sales in neighboring communities would be nearly 
$41 million, and personal income would be about $78 million higher than in the future-without. 

Total direct agricultural employment in the four subareas would be about 2,500 jobs higher with 
the recommended plan than without it. Additional employment of more than 3,200 person-years 
would occur both in industries that serve agriculture and in the general economies of nearby 
communities. The overall improvement in employment would exceed 5,700 jobs. 



160 



Future-Without 
Conditions 


Recommended 
Plan 


24,000 


55.000^ 


28,000 


49,000 


1,965,000 
345,000 


2,325,000 
783,000 


460,000 





75,000 



Table 46. INCREASE IN RETAIL SALES, INCOME, AND EMPLOYMENT FROM 

FUTURE-WITHOUT CONDITIONS TO THE RECOMMENDED PLAN 

FOR SELECTED SUBAREAS, 2040 



Item 



Increase in irrigated crop 
area (1,000 acres) 

Crop value maintained 

Direct retail sales 

Indirect and induced retail 
sales 

TOTAL RETAIL SALES 

Direct personal income 

Indirect and induced personal 

income 

TOTAL PERSONAL INCOME 

Direct employment 

Indirect and induced 

employment 

TOTAL EMPLOYMENT 



Grasslands 


Westlands 


Tulare 


Kern 


36 


101 


170 


53 


23,788 


85.862 


139,332 


35,877 


865 


3,125 


5,071 


1,305 


2,529 


9,158 


14,932 


3,836 


3,394 


12,283 


20,003 


5,141 


2,984 


10,888 


17,975 


4,590 


4,054 


19,635 


11,417 


5,975 


7,038 


30,523 


29,392 


10,565 


223 


780 


1,206 


319 


568 


1,423 


812 


414 



791 



2,203 



2,018 



733 



Total 
360 

284,859 
10.366 
30,455 

40,821 

36,437 
10.565 

77,518 
2,528 
3,217 

5,745 



Note: Crop value, retail sales, and income are in 1,000s (1990) of dollars per year, and employment is in person-years per year. 



161 



REFERENCES CITED 



The following abbreviations identify organizations that are cited in the text of this report. 

AWMS Agricultural Water Management Subcommittee, Interagency Technical Advisory Committee 

CDFA California Department of Food and Agriculture 

CVRWQCB California Regional Water Quality Control Board, Central Valley Region 

DWR California Department of Water Resources 

IDP Interagency Drainage Program 

NRC National Research Council 

RMI Resources Management International, Inc. 

SJVDP San Joaquin Valley Drainage Program 

SWRCB State Water Resources Control Board 

UCCC University of California Committee of Consultants on Drainage Water Reduction 

USER U.S. Bureau of Reclamation 

USEPA U.S. Environmental Protection Agency 

Altringer, P. B.; Larsen, D. M.; and Gardener, K. R., 1987, A Biohydrometallur^cal Approach to 
Selenium Removal: U.S. Bureau of Mines, Salt Lake City, Utah. 

Archibald, Sandra, June 1990, Economic Profile of Agriculture in the Westside of the San Joaquin Valley: 
Stanford University. A report prepared for the San Joaquin Valley Drainage Program, Sacramento, 
California. 

Agricultural Water Management Subcommittee, Interagency Technical Advisory Committee, October 
1987, Farm Water Management Options for Drainage Reduction: San Joaquin Valley Drainage 
Program, Sacramento, California. 

Belitz, K., 1988, Character and Evolution of the Ground-Water Flow System in the Central Part of the 
Western San Joaquin Valley, California: U.S. Geological Survey, Open File Report 87-573. 

Boyle Engineering Corporation, June 1990, Demonstration of Emerging Irrigation Technology: Semiannual 
Progress Report. A report prepared for the California Department of Water Resources and the 
State Water Resources Control Board, Sacramento, California.. 

. December 1989a, Demonstration of Emerging Irrigation Technology: Semiannual Progress 

Report. A report prepared for the California Department of Water Resources and the State Water 
Resources Control Board, Sacramento, California. 

. June 1989b, Demonstration of Emerging Irrigation Technology: Semiannual Progress Report. A 

report prepared for the California Department of Water Resources and the Slate Water Resources 
Control Board, Sacramento, California. 

February 1988, Report on Selenium Selectivity in Ion Exchange Resins. A report prepared for 
the San Joaquin Valley Drainage Program, Sacramento, California. 



163 



Bradford, D. E; Drezner, D.; Shoemaker, J. D.; and Smith, L., June 1989, Evaluation of Methods to 

Minimize Contamination Hazards to Wildlife Using Agricultural Evaporation Ponds in the San Joaquin 
Valley. California. A report prepared for the California Department of Water Resources, 
Sacramento, California. 

Burt, C. M.; and Katen, K., March 1988, Westside Resource Conservation District 1986187 Water 

Conservation and Drainage Reduction Program. A technical report to the California Department of 
Water Resources, Office of Water Conservation, Sacramento, California. 

California Department of Food and Agriculture, March 1988, The Agroforestry Demonstration Program in 
the San Joaquin Valley: Progress Report. A report prepared for the San Joaquin Valley Drainage 
Program, Sacramento, California. 

California Department of Water Resources, September 1989, Management of the California 
State Water Project, Bulletin 132-89: Sacramento, California. 

. 1987, Map of Present and Potential Drainage Problem Areas, Western San Joaquin Valley, 



California: Sacramento, California. 
. October 1986, Technical Information Record on the Physical/ Chemical Pretreatment System at 



the Los Bancs Demonstration Desalting Facility: Sacramento, California. 
. 1957, The California Water Plan, Bulletin 3: Sacramento, California. 



California Regional Water Quality Control Board, Central Valley Region, October 1988a (Draft), 
Amendments to the Water Quality Control Plan for the San Joaquin Basin (5C) for the Control of 
Agricultural Subsurface Drainage Discharges: Sacramento, California. 

. October 1988b, Uranium Levels in Water in Evaporation Basins Used for the Disposal of 



Agricultural Subsurface Drainage Water in the San Joaquin Valley, California: Sacramento, California. 
. July 1988c, Water and Sediment Quality in Evaporation Basins Used for Disposal of 



Agricultural Subsurface Drainage Water in the San Joaquin Valley, California: Sacramento, California. 

CH2M Hill, 1990 (draft). Detailed Options Descriptions. A report prepared for the U.S. Bureau of 
Reclamation, Sacramento, California. 

. October 1988, San Joaquin Valley Hydrologic and Salt Load Budgets. A report prepared for 



the San Joaquin Valley Drainage Program, Sacramento, California. 

Chilcott, J.; Westcot, D.; and Belden, K., 1988, Water Quality Survey of Tile Drainage Discharges in the 
San Joaquin River Basin: California Regional Water Quality Control Board, Central Valley Region, 
Sacramento, California. 

Coontz. N. D., March 1990a, Organizations and Institutions: Agricultural Drainage-Related Water 
Management in the Kings River Region, California. An SJVDP Technical Information Record. 

. February 1990b, Local Initiatives to Manage Drainage and Related Problems in the San 



Joaquin Valley. An SJVDP Technical Memorandum. 
. March 1989, Agricultural Drainwater Management Organizations in the Drainage Problem 



Area of the Grasslands Area of the San Joaquin Valley: Ebasco Services, Inc., Sacramento, California. 
A report prepared for the San Joaquin Valley Drainage Program, Sacramento, California. 



164 



Davis, E. A.; Maier, K. J.; and Knight, A. W., January-February 1988, The Biological Consequences of 
Selenium in Aquatic Ecosystems: California Agriculture, v. 42, p. 18-29. 

Deverel, S. J.; and Gallanthine, S. K., 1988, Relation of Salinity and Selenium in Shallow Ground Water to 
Hydrologic and Geochemical Processes, Western San Joaquin Valley, California: U.S. Geological 
Survey, Open File Report 88-336. 

Deverel, S. J.; Fujii, Roger; Izbicki, J. A.; and Fields, J. C, 1984, Areal Distribution of Selenium and Other 
Inorganic Constituents in Shallow Ground Water of the San Luis Drain Service Area: U.S. Geological 
Survey, Water-Resources Investigations Report 84-4319. 

Dubrovsky, N. M.; and Neil, J. M., 1990, San Joaquin Valley RASA Phase II: Regional to Site-Specific 

Approaches to Evaluating Regional Geochemical Processes and Trace-Element Distribution. (Abstract) 
Paper presented at the Annual Meeting of the Association of Ground Water Scientists and 
Engineers. 

EPOC AG, November 1987, Removal of Selenium from Subsurface Agricultural Drainage by an Anaerobic 
Bacterial Process. A final report on continued operation of the Murrieta Pilot Plant. Submitted to 
the California Department of Water Resources, Sacramento, California. 

Frankenberger, W. T; and Karlson, U., March 1989, Microbial Volatilization of Selenium at Kesterson 
Reservoir: Interim Report. A report prepared for the U.S. Bureau of Reclamation, Sacramento, 
California. 

Frankenberger, W. T; and Thompson-Eagle, E. T, September 1989, In Situ Volatilization of Selenium 
from Evaporation Ponds. A report prepared for the San Joaquin Valley Drainage Program, 
Sacramento, California. 

Gilliom, R. J., et al., 1989a, Preliminary Assessment of Sources, Distribution, and Mobility of Selenium in the 
San Joaquin Valley, California: U.S. Geological Survey, Water-Resource Investigation Report 

No. 88-4186. 

1989b (draft). Preliminary Simulation of Effects of Land Retirement on Drainage Problems: 



U.S. Geological Survey, unpublished report. 

Gilliom, R. J.; and Clifton, D. G., 1987, Organochlorine Pesticide Residues in Bed Sediments of the 
San Joaquin River and Its Tributary Streams, California: U.S. Geological Survey, Open File 
Report 87-531. 

Hanna, G. R; Kipps, J. A.; and Owens, L. R, October 1990, Agricultural Drainage Treatment Technology 
Review. A report prepared for the San Joaquin Valley Drainage Program, Sacramento, California. 

Harza Environmental Services, Inc., May 1989, Fundamental Aspects of Selenium Removal by Harza 

Process. A report prepared for the San Joaquin Valley Drainage Program, Sacramento, California. 

Interagency Drainage Program, June 1979, Agricultural Drainage and Salt Management in the 
San Joaquin Valley: Sacramento, California. 

Klasing, S. A.; and Pilch, S. M., August 1988, Agricultural Drainage Water Contamination in the 

San Joaquin Valley: A Public Health Perspective for Selenium. Boron, and Molybdenum. A report 
prepared for the San Joaquin Valley Drainage Program, Sacramento, California. 



165 



Klasing, S. A.; Wisniewski, J. A.; Pilch. S. M.; and Anderson, S. A., 1990, Agricultural Drainage Water 
Contamination in the Western San Joaquin Valley: a Public Health Perspective for Arsenic. 
Nitrates/Nitrites, Mercury, Uranium, and Vanadium. A report prepared for the San Joaquin Valley 
Drainage Program, Sacramento, California. 

Loomis, J.B.; Hanemann, W.M.; and Wegge, T.C., September 1990, Environmental Benefits Study of the 
San Joaquin Valley's Fish and Wildlife Resources. A report prepared for the San Joaquin Valley 
Drainage Program, Sacramento, California. 

Martin, P. L., July 1987, California's Farm Labor Market: University of California Agricultural Issues 
Center, Issues Paper No. 87-1, Davis, California. 

Mines, Richard; and Martin, P. L., July 1986, A Profile of California Farmworkers: University of 
California, Giannini Information Series No. 86-2. 

National Research Council, 1989, Irrigation-Induced Water Quality Problems: What Can Be Learned from 
the San Joaquin Valley Experience: National Academy Press, Washington, D.C. 

Neal, R. H.; and Sposito, G., December 1988, Attenuation of Selenium Draining from Irrigated Seleniferous 
Agricultural Soils. A report prepared for the San Joaquin Valley Drainage Program, Sacramento, 
California. 

Nishimura, George; and Baughman, Sheryl, January 1989, Regulating Timing of Salt Entry to the 
San Joaquin River. An SJVDP Technical Information Record. 

Ogden, G. R., March 1988, Agricultural Land Use and Wildlife in the San Joaquin Valley. 1769-1930: An 
Overview: SOLO Heritage Research. A report prepared for the San Joaquin Valley Drainage 
Program, Sacramento, California. 

Oswald, W. J., el al., January 1990, Second Annual Report Microalgal-Bacterial Treatment for Selenium 
Removal from San Joaquin Valley Drainage Waters. A report prepared for the San Joaquin Valley 
Drainage Program, Sacramento, California. 

Page, R.W., 1986, Geology of the Fresh Ground-Water Basin of the Central Valley, California, with Texture 
Maps and Sections: U.S. Geological Survey, Professional Paper 1401-c. 

. 1983, Geology of the Tulare Formation and Other Continental Deposits, Kettieman City Area, 



San Joaquin Valley, California, with a Section on Groundwater Management Considerations and 
Use of Texture Maps: U.S. Geological Survey, Water Resources Investigation Report 83-4000. 

Phillips, S., 1990 (unpublished data). Preliminary Results from a USGS Regional Aquifer Model of the 
Alluvial Fans on the West Side of the San Joaquin Valley. 

Quinn, N. W. T; Swain, W. C; and Hansen, D. L., August 1990, Assessment of Ground-Water Pumping as a 
Management Option in Drainage Problem Areas of the Western San Joaquin Valley. An SJVDP Technical 
Information Record. 

Resources Management International, Inc., June 1990 (draft), Agroforestry Biomass Fuel Assessment. A 
report in preparation for Westlands Water District, Fresno, California. 

. August 1989, Concept Evaluation Report for the Westlands Water District Selenium 

Removal I Cogeneration Project. A report prepared for the Westlands Water District, Fresno, California. 



166 



Rhoades, J. D., 1987, Reuse of Drainage Water for Irrigation: Results of Imperial Valley Study: I Hypothesis, 
Experimental Procedures and Cropping Results: U.S. Salinity Laboratory, USDA-ARS, Riverside, 
California. 

Rowley, L. H.; Moody, C. D.; and Murphy, A. R, 1990 (Draft), Selenium Removal with Ferrous Hydroxide: 
Executive Summary. A report in preparation for the San Joaquin Valley Drainage Program, 
Sacramento, California. 

San Joaquin Valley Drainage Program, October 1990, Fish and Wildlife Resources and Agricultural 
Drainage in the San Joaquin Valley, California: Sacramento, California. 

. August 1989, Preliminary Planning Alternatives for Solving Agricultural Drainage and 



Drainage-Related Problems in the San Joaquin Valley: Sacramento, California. 

. 1988, Formulating and Evaluating Drainage Management Plans for the San Joaquin Valley. 

An SJVDP Technical Information Record. 

. June 1987, Developing Ahemative Future-Without Project Scenarios for Agricultural Drainage 



and Drainage-Related Problems in the San Joaquin Valley, based on Workshops of February and 
March 1987: Sacramento, California. 

Schmidt, K. D., 1989, Results of 14 Day Aquifer Tests near Mendota. Unpublished report prepared for the 
San Joaquin Valley Drainage Program, Sacramento, California. 

. 1988, Report of Aquifer Tests for Shallow Wells in Firebaugh-Mendota Area. Unpublished 



report prepared for the San Joaquin Valley Drainage Program, Sacramento, California. 

Schroeder, E. D.; Ergas, S.; Lawver, R.; and Pfeiffer, W. J. C, December 1989, Mechanism of Selenium 
Removal from San Joaquin Valley Agricultural Drainage Water. A report prepared for the San 
Joaquin Valley Drainage Program, Sacramento, California. 

State Water Resources Control Board, August 1987, Regulation of Agricultural Drainage to the San 
Joaquin River: SWRCB Order No. W.Q. 85-1, Technical Committee Report: Sacramento, 
California. 

Swain, D. G., September 1990, Documentation of the Use of Data, Analysis, and Evaluative Processes That 
Resulted in the SJVDP Recommended Plan. An SJVDP Technical Information Record. 

Swain, W. C, August 1990a, Basis of Calculation of Forecasts and Extent of Shallow Ground Water Table, 
Westside San Joaquin Valley. An SJVDP Technical Memorandum. 

. August I990h, Development of Shallow Ground-Water Quality Maps. An SJVDP Technical 



Memorandum. 

. August 1990c, Comments on Soil Salinities in the Grasslands Problem Area and the Northern 

Subarea, in Response to a Letter of July 20, 1990, from the South Delta Water Agency. An 
SJVDP Technical Memorandum. 

Tanji, K. K., in press, "Chemistry of Toxic Elements (As, B, Mo, Se) Accumulating in Agricultural 
Evaporation Ponds," in Symposium Proceedings, U.S. Committee on Irrigation Drainage, Ottawa, 
Canada, June 8, 1989. 

Tanji, K. K.; and Dahlgren, R. A., April 1990, Efficacy of Evaporation Ponds for Disposal of Saline 

Drainage Waters: University of California, Davis, Department of Land, Air, and Water Resources. 
A report to the California Department of Water Resources, Sacramento, California. 



167 



Thomas, G. A.; and Leighton-Schwartz, M. T, 1990, Legal and Institutional Structure for Managing 
Agricultural Drainage in the San Joaquin Valley: Designing a Future. A report prepared for the 
San Joaquin Valley Drainage Program, Sacramento, California. 

Tidball, R. R.; Severson, R. C; Gent, C. A.; and Riddle, G. O., 1986, Element Associations in Soils of the 
San Joaquin Valley, California: U.S. Geological Survey, Open File Report No. 86-583, Denver, 
Colorado. 

University of California Committee of Consultants on Drainage Water Reduction, February 1988, The 

Evaluation of Water Quality Criteria for Selenium, Boron, and Molybdenum in the San Joaquin River Basin. 
A Report Prepared for the University of California Salinity/Drainage lask Force and the University of 
California Water Resources Center, Davis, California. 

U.S. Bureau of Reclamation, 1989, 7990 Irrigation Water Rates: Central Valley Project, California: 

Department of the Interior, Bureau of Reclamation, Mid-Pacific Region, Sacramento, California. 

. 1964, Addendum to Alternative Solutions for Drainage: Sacramento, California. 

. 1962, Alternative Solutions for Drainage: Sacramento, California. 



. May 1955, San Luis Unit, Central Valley Project: A Report on the Feasibility of Water Supply 

Development: Sacramento, California. 

U.S. Environmental Protection Agency, September 1987, Ambient Water Quality Criteria for 
Selenium - 1987: USEPA Publication No. 440/5-87-006, Washington, DC. 

Westlands Water District, 1988, Annual Report: March 1, 1987 to February 29, 1988: Westlands Water 
District, Fresno, California. 



168 



SELECTED BIBLIOGRAPHY 



Policy Reports, Technical Reports, and IVIemoranda by Staff and Contractors of the 
San Joaquin Valley Drainage Program are available through the SJVDP Data Directory. 
Phone (916) 978-4981 or FTS 460-4981 



SAN JOAQUIN VALLEY DRAINAGE PROGRAM REPORTS 

POLICY REPORTS (approved by Policy and Management Committee) 

San Joaquin Valley Drainage Program, October 1990, San Joaquin Valley Drainage Program Final Report: 
Sacramento, California. 

. June 1990, San Joaquin Valley Drainage Program Draft Final Report: Sacramento, 



California. 



_. August 1989, Preliminary Planning Alternatives for Solving Agricultural Drainage and 



Drainage-Related Problems in the San Joaquin Valley: Sacramento, California. 
. December 1987, Developing Options: An Overview of Efforts to Solve Agricultural Drainage 



and Drainage-Related Problems in the San Joaquin Valley: Sacramento, California. 
. February 1987, Prospectus (with separate Appendixes volume): Sacramento, California. 



TECHNICAL REPORTS 

Lee, E.; Nishimura, George; and Hansen, Henry, September 1988, Agricultural Drainage Water 

Treatment, Reuse, and Disposal in the San Joaquin Valley of California: Part I, Treatment Technology, 
and Part II, Reuse and Disposal: Sacramento, California. 

Moore, S. B.; Detwiler, S. J.; Winckel, Joy; and Weegar, Mark, November 1989, Biological Residue Data 
for Evaporation Ponds in the San Joaquin Valley, California: Sacramento, CalUbrnia. 

San Joaquin Valley Drainage Program, September 1990, Fish and Wildlife Resources and Agricultural 
Drainage in the San Joaquin Valley, California: Sacramento, California. 

Swain, D.G.; Stroh, Craig; Quinn, N.W.T.; Kasower, Steven; and Horton, Robert, October 1988, 
Formulating and Evaluating Drainage Management Plans for the San Joaquin Valley: Sacramento, 
California. 



169 



REPORTS IN THE TECHNICAL INFORMATION RECORD SERIES 

Coontz, N.D.. March 1990, Organizations and Institutions: Agricultural Drainage-Related Water 
Management in the Kings River Region, California: Sacramento, California. 

Nishimura, George, August 1986, Use of Agricultural Drainage Water for Power Plant Cooling: 
Sacramento, California. 

Nishimura, George; and Baughman, Sheryl, January 1989, Regulating Timing of Salt Entry to the San 
Joaquin River: Sacramento, California. 

. August 1988, Agricultural Drainage Conditions in the San Joaquin Valley: Sacramento, 



California. 



Nishimura, George; and Hansen, Heniy, June 1989, Agroforestry in the Upland Area of the Westlands 
Subarea: Sacramento, California. 

Nishimura, George; and Lee, Ed, March 1989, Hazardous and Designated Waste Disposal: Sacramento, 
California. 

. November 1988, Structural Options in the Grasslands Subarea: Sacramento, California. 



Puckett, Larry, May 1990, Water Management for Fish and Wildlife: Sacramento, California. 

Quinn, N.W.T, August 1990, Overview of the Use of the Westside Agricultural Drainage Economics Model 
(WADE) for Plan Evaluation: Sacramento, California. 

Stroh, Craig; Dinar, Ariel; and Quinn, N.W.T, July 1990, Assessment of Land Retirement as a Strategy for 
Long-Term Management of Agricultural Drainage and Drainage-Related Problems in the Western San 
Joaquin Valley of California: Sacramento, California. 

Swain, D.G., September 1990, San Joaquin Valley Drainage Program - Recommended Plan Supporting 
Document: Sacramento, California. 

MEMORANDA ON TECHNICAL PROCEDURES AND RESULTS OF ANALYSES (usually 
titled Memoranda to San Joaquin Valley Drainage Program Data Directory) 

Kasower, Steven; and M'Marete, Marangu, September 1990, Development of the Dynamic Agro-Economic 
Soil Salinity (DASS) Model 

Lee, Ed, April 1988, Documentation of Out-of-Valley Disposal Studies. (Prepared in response to a 
directive of the SJVDP Policy and Management Committee, August 17, 1987.) 

Nishimura, George, September 1990, Treatment and Reuse of Drainage Water from the Grasslands Subarea 
in Western Merced and Madera Counties. 

. November 1989, Drainage Water Reuse in the East Side of the San Joaquin Valley. 

. October 1989, Facilities to Transport Replacement Water to Refuges in the San Joaquin Valley. 



Nishimura, George; and Hansen, Henry, August 1990, Treatment and Disposal Alternative for the Northern 
and Grassland Subarea. 

. August 1990, Treatment and Disposal Alternative for the Westlands, Tulare, and Kern Subareas. 



Nishimura, George; and Horton, Robert, August 1989, Considerations in the Retirement of Farmland from 
Irrigated Agriculture in the San Joaquin Valley. 



170 



Quinn, N.W.T.; August 1990, Assessment of Ground-Water Pumping as a Management Option in Drainage 
Problem Areas of the Western San Joaquin Valley. 

. August 1990, Simulation of Water Quality Over Time from a Pumped Well Used to Lower 



Saline High Water. 

Stroh, Craig, August 1990, Documentation of Cost Estimates, SJVDP Recommended Plan. 

Swain, W.C., August 1990, Development of Shallow Ground-Water Quality Maps. 

Yates, Marvin, August 1990, Documentation of the Development and Use of the QA System of 
SJVDP. 



MISCELLANEOUS REPORTS 

San Joaquin Valley Drainage Program, January 1988, Public Involvement Plan: Sacramento, California. 

. June 1987, Developing Alternative Future-Without-Project Scenarios for Agricultural Lands 

and Wetlands in the San Joaquin Valley: Sacramento, California. 

. May 1987, On-Farm and Wetland Management Practices: Summary of Workshops: 

Sacramento, California. 

. December 1986, Project Data Directory: Sacramento, California. 

. October 1986, San Joaquin Valley Drainage Program Directory: Sacramento, California. 

. October 1985 - June 1990, San Joaquin Valley Drainage Program Status Reports: 



No. 1 -October 1985 
No. 2 - November 1985 
No. 3 - March 1986 
No. 4 - July 1986 
No. 5 - September 1986 
No. 6 - January 1987 



No. 7 - April 1987 
No. 8 - July 1987 
No. 9 - October 1987 
No. 10 - February 1988 
No. 11 - September 1988 
No. 12 - January 1989 



No. 13 - May 1989 
No. 14 - August 1989 
No. 15 - December 1989 
No. 16 - March 1990 
No. 17 - June 1990 



SUMMARIES OF PUBLIC INFORMATION MEETINGS 

September 25 - October 3, 1989 (Bakersfield, Lost Hills, Corcoran, Fresno, Mendota, 
Los Banos, Patterson, and Oakland). 

July 23-27, 1990 (Sacramento, San Francisco, Los Banos, Fresno, and Bakersfield). 



171 



CITIZENS ADVISORY COMMITTEE MEETING MINUTES 



March 5, 1987 - Stockton 
April 10, 1987 - Santa Nella 
May 22, 1987 - Pleasanton 
June 22, 1987 - Patterson 
July 27, 1987 - Livermore 
September 28-29 1987 - Coalinga 
January 11. 1988 - Oakland 
February 11, 1988 - Santa Nella 
March 28„ 1988 - Tracy 
April 25, 1988 - Livermore 
May 23, 1988 - Stockton 
June 28, 1988 - Coalinga 
August 29, 1988 - Stockton 



September 26, 1988 - Stockton 
February 13, 1989 - Stockton 
AprU 3, 1989 - Stockton 
April 3, 1989 - Stockton 
July 31. 1989 - Byron 
September 11, 1989 - Stockton 
November 13, 1989 - Los Banos 
January 17. 1990 - Sausalito 
April 18, 1990 - Coalinga 
May 30, 1990 - Stockton 
July 16, 1990 - Stockton 
August 13, 1990 - Stockton 



POLICY AND MANAGEMENT COMMITTEE MEETING MINUTES 



1985 



1986 



1987 



August 19 


January 8 


February 23 


October 21 


January 21 


April 2 


November 12 


February 13 


June 15 


November 25 


March 6 


August 17 


December 9 


April 2 


October 21 


December 16 


April 29 
May 26 
June 26 
August 28 
October 8 
November 12 




1988 


1989 


1990 


January 4 


March 24 


May 7 


March 11 


July 7 


June 13 


May 9 


December 18 


August 15 


May 23 


August 1 


September 22 


December 5 







172 



CONTRACTORS' REPORTS PREPARED FOR 

OR IN COOPERATION WITH 

THE SAN JOAQUIN VALLEY DRAINAGE PROGRAM 



In addition to the publications listed below, the SJVDP Data Directory includes an extensive 
bibliography of U.S. Geological Survey and U.S. Fish and Wildlife Service reports based on 
investigations conducted for or in cooperation with the San Joaquin Valley Drainage Program. 

Archibald, Sandra, June 1990, Economic Profile of Agriculture in the Westside of the San Joaquin Valley: 
Stanford University. 

Boyle Engineering Corporation, December 1988, Evaluation of Unlined Ditch and Reservoir Seepage 
Losses in Westlands Water District. 

. October 1986, Evaluation of On-Farm Agricultural Management Alternatives. 



Bradford, D.F.: and Little. R.J., January 1990, Techniques to Restore Fish and Wildlife Habitats 
Contaminated by Subsurface Agricultural Drainage Water: Ebasco Services, Inc. 

. January 1990, Techniques to Restore Fish and Wildlife Habitats Contaminated by Subsurface 



Agricultural Drainage Water, Appendix E: Ebasco Services, Inc. 

Brown and Caldwell Consulting Engineers, April 1987, Screening Potential Alternative Geographic 
Disposal Areas. 

California Department of Food and Agriculture, March 1988, The Agroforestry Demonstration Program in 
the San Joaquin Valley. 

. February 1986, Selenium Survey in Animals and Animal Products. 



. November 1985 (draft). Monitoring Selenium. Nickel, and Chromium Concentrations in 

Agricultural Commodities of the Western San Joaquin Valley, 1984. 

Campbell, M.B., September 1988, Ownership and Recreational Use of Wetlands in the Grassland Water 
District and Refuges of the Central San Joaquin Valley: University of California, Davis. 

CH2M Hill, September 1989, Irrigation Systems Costs and Performance in the San Joaquin Valley. 

. October 1988, San Joaquin Valley Hydrologfc and Salt Load Budgets. 

. January 1986, Reverse Osmosis Desalting of the San Luis Drain, Conceptual-Level Study. 

Coontz, N.D., March 1989, Agricultural Drainwater Management Organizations in the Drainage Problem 
Area of the Grasslands Area of the San Joaquin Valley: Ebasco Services, Inc. 

Cooper, Joseph; and Loomis, John, November 1988, The Economic Values to Society and Landowners of 
Wildlife in San Joaquin Valley Agroforestry Plantations: California Department of Food and 
Agriculture and University of California, Davis. 

Dinar, Ariel; and Campbell, M.B., August 1990, Farts I and III, Adoption of Improved Irrigation and 
Drainage Reduction Technologies in the Westside of the San Joaquin Valley: University of California, 
Riverside, and Management Systems Research. 

Doroshov, S.I.; and Wang, Y.L.. August 1984, The Effect of Subsurface Agricultural Drainage Water on 
Larval Striped Bass, Morone saxatilis (Walbaum): University of California, Davis. 



173 



EA Engineering, Science, and Technology, Inc., September 1985, Procedure and Testing Protocol for 
Recommending Modifications to Effluent Limits Which are Set for the Discharge of Subsurface 
Agricultural Drainage Waters in California. 

Frankenbcrger, W.T.; and Thompson-Eagle, E.T., September 1989, Study of In Situ Volatilization of 
Selenium, 11. Evaporation Ponds: University of California, Riverside. 

. September 1989, Study of In Situ Volatilization of Selenium, II. Evaporation Ponds, 



(Executive Summary): University of California, Riverside. 

Frankenbcrger, W.T.; and Tkmaki, S., March 1989, Environmental Biochemistry of Arsenic: University of 
California, Riverside. 

Gaines, Raymond, Juno 1988, West San Joaquin Valley Agricultural Setting, Boyle Engineering 
Corporation. 

Outer, G.A., February 1988, Selenium Selectivity in Ion-Exchange Resins, Boyle Engineering Corporation. 

Hanna, G. P.; Kipps, J. A.; and Owens, L. R, October 1990, Agricultural Drainage Treatment Technology 
Review. 

Harza Environmental Services, Inc., May 1989, Fundamental Aspects of Selenium Removal by Harza 
Process. 

Herrmann, C.C., August 1985, Removal of Ionic Selenium from Water by Ion Exchange: Review of 
Literature and Brief Analysis: University of California, Berkeley. 

Klasing, S.A.; and Pilch, S.M., August 1988, Agricultural Drainage Water Contamination in the San 
Joaquin Valley: A Public Health Perspective: Health Officers Association of California. 

J.M. Lord, Inc., October 1989, Phase III Report, Study of Innovative Techniques to Reduce Subsurface 
Drainage Flows. 

. March 1989, Phase II Report, Study of Innovative Techniques to Reduce Subsurface Drainage 



Flows. 



_. November 1987. Phase I Report, Study of Innovative Techniques to Reduce Subsurface 



Drainage Flows. 

Miller, J.R., January 1986, An Estimate of the Value of a Waterfowl Hunting Day in the Central Valley of 
California: University of Utah. 

National Academy of Science/National Research Council, 1989, Irrigation Induced Water-Quality 

Problems: What Can Be Learned from the San Joaquin Valley Experience: National Academy Press, 
Washington, D.C. 

Neal, Rosemary; and Sposito, Garrison, December 1988, Attenuation of Selenium Draining from Irrigated 
Seleniferous Agricultural Soils: University of California, Riverside. 

Ogden, G.R., March 1988, Agricultural Land Use and Wildlife in the San Joaquin Valley. 1769-1930: An 
Overview: SOLO Heritage Research. 

Oswald. W.J., August 1985, Potential for Treatment of Agricultural Drain Water with Microalgal-Bacterial 
Systems. 

Price, M.K.; and Eisenhauer, R.J., July 1988, Report on Selenium Process Testing: U.S. Bureau 
of Reclamation. 



174 



Prokopovich, N.P., April 1989, Irrigation History of the West-Central San Joaquin Valley. 
. April 1989, Lithology and Physical Properties of Alluvium in the West-Central 



San Joaquin Valley. 

SOA, Inc., November 1988, Microalgal-Bacterial Selenium Reduction System Development Pilot Plant. 

SRI International, May 1985, Chronic Toxicity of San Luis Drain Effluent to Neomvsis mercedis. 
Final Report. 

Thomas, G. A.; and Leighton-Schwartz, M. T, 1990, Legal and Institutional Structure for Managing 
Agricultural Drainage in the San Joaquin Valley: Designing a Future: Natural Heritage Institute. 

URS Corporation, October 1986, Deep-Well Injection of Agricultural Drain Waters, Summary Report and 
Technical Appendices: Westlands Water District, Fresno, California. 

Water Education Foundation, 1986, Layperson 's Guide to Agricultural Drainage: Sacramento, California. 

Wichelns, Dennis, March 1988, Farm-Level Analysis of Irrigated Crop Production in Areas with Salinity 
and Drainage Problems: University of Rhode Island. 



175 



ABBREVIATIONS 

Ac: acre 

Acre-ft: acre-feet 

AF: acre-feet 

CCC: Commodity Credit Corporation 

CSWRCB: California State Water Resources Control Board 

CVP: Central Valley Project 

CVRWQCB: California Regional Water Quality Control Board, Central Valley Region 

DFG: California Department of Fish and Game 

DWR: California Department of Water Resources 

EC: electrical conductivity 

EPA: U.S. Environmental Protection Agency 

EPOC AG: EPOC Agricultural Corporation 

gpm: gallons per minute 

GW: ground water 

ITAC: Interagency Technical Advisory Committee, San Joaquin Valley Drainage Program 

k: thousand 

mgd: million gallons per day 

NWR: National WUdlife Refuge 

ppb: parts per billion 

ppm: parts per million 

SJVDP: San Joaquin Valley Drainage Program (1984-1990) 

SWP: State Water Project 

SWRCB: California State Water Resources Control Board 

TDS: total dissolved solids 

UC: University of California 

USER: U.S. Bureau of Reclamation 

USFWS: U.S. Fish and Wildlife Service 

USGS: U.S. Geological Survey 

WA: wildlife area managed by the State of California 

yd^: cubic yards 

> : greater than 

>: greater than or equal to 

< : less than 

<: less than or equal to 



177 



GLOSSARY 



Acre -foot: The quantity of water required to cover 1 acre to a depth of 1 foot. Equal to 325,851 
gallons or 43,560 cubic feet. 

Adsorption: The surface retention of solid, liquid, or gas molecules, ions, or atoms by a solid or liquid. 

Aerobic: Referring to a condition requiring the presence of oxygen. Aerobic bacteria require free 
oxygen for the metabolic breakdown of materials. 

Agroforestry: As used in this report, it is the practice of growing certain types of trees with drainage 
water. The trees act to dispose of applied drainage and shallow ground water through foliar 
evapotranspiration and at the same time produce a marketable commodity. 

Alluvium: A general term for clay, silt, sand, gravel, or similar unconsolidated material deposited 
during comparatively recent geologic time by a body of running water. 

Alluvial fan: A low, outspread, relatively flat to gently sloping mass of stream deposits, shaped like an 
open fan or a segment of a cone deposited by a stream, especially in a semiarid region at the place 
where it issues from a narrow mountain valley upon a plain or broad valley. 

Anaerobic: Referring to the condition of existing in the absence of oxygen. Anaerobic bacteria can 
survive in the partial or complete absence of air. 

Aquaculture: As used in this report, refers to the potential use of drainage water for growth of aquatic 
organisms (fish, etc.) that could have product marketability. 

Aquifer: An underground geologic formation that stores and transmits water and yields significant 
quantities of water to wells and springs. 

Attenuation: In the context of this report, refers to the reduction of the amount of metal species 
transmitted through a soil column. Research has been conducted on the attenuation of selenium. 

Basin trough: A long, sediment-filled depression at the center of the valley. 

Bioaccumulation: The uptake and accumulation of a chemical by plants and animals directly from the 
environment (that is, from water, sediment, soil, or air) or through the diet. See Bioconcentration 
and Biomagnification. 

Bioconcentration: The uptake and accumulation of a chemical by plants and animals directly from the 
environment, resulting in whole-body concentrations greater than those found in the environment. See 
Bioaccumulation and Biomagnification. 

Biomagnification: The uptake and accumulation of a chemical by plants and animals through their 
diet, resulting in whole-body concentrations that increase at successively higher trophic levels of the 
food chain. See Bioaccumulation and Bioconcentration. 

Biomass: As used in this report, refers to plant material that has been grown in drainage water and 

is suitable for use as a fuel, such as in cogeneration processes. 

Cogeneration: A process using waste heat from the thermal generation of energy to evaporate 

drainage water. 

Confined aquifer: An aquifer bounded above and below by impermeable beds or beds of distinctly 

lower permeability than the aquifer itself. 

Conjunctive use: A resource use or management plan in which surface and ground water supplies are 

used in a manner to maximize use from both without degradation of either. 



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Contamination: The addition to a given medium, such as water, of substances that adversely affect its 
beneficial use. 

Critical year: A year is classified as critical when unimpaired runoff to the San Joaquin River and key 
tributaries, as described in Department of Water Resources' Bulletin 120, is less than 3.37 million 
acre-feet. However, if the previous year was classified as critical, a year is rated as critical when 
unimpaired runoff is less than 4.13 million acre-feet. 

Deep percolation: The downward percolation of water past the lower limit of the root zone of plants, 

usually more than 5 feet below the surface. 

Delta: A low, nearly fiat alluvial tract of land formed by deposits at or near the mouth of a river. In 
this report. Delta usually refers to the delta formed by the Sacramento and San Joaquin Rivers. 

Drainage problem area: A land area characterized by waterlogging and related water-quality 
problems. Includes land areas now drained or land areas that likely will require drainage. 

Drainage water: See Subsurface drainage water. 

Endangered species: Any species or subspecies of bird, mammal, fish, amphibian, reptile, or plant 
which is in serious danger of becoming extinct throughout all, or a significant portion of, its range. 

Electrical conductivity (EC): The ability of a particular parcel of water to conduct electricity. The EC 
of a water sample is an indirect measure of the total dissolved solids (TDS) or salinity of the sample. 
Units of reporting are Siemens, which are equivalent to the older units, mhos. Microsiemens per 
centimeter are abbreviated as ^S/cm. 

Evaporation: The change of a substance from the solid or liquid phase to the gaseous (vapor) phase. 

Evapotranspiration: Water lost as vapor through the combined processes of evaporation from soil 
surface and transpiration from plants. 

Facultative bacteria: Microorganisms capable of adaptive response to varying environments (for 
example, adaptive to aerobic or anaerobic conditions). 

Furrow: A long, narrow, shallow trench made in the ground by a plow or other implement. 

Halophytes: Plants that are well adapted to growing in a saline soil environment. 

Hydraulic connections: The situation existing between two aquifers whereby the openings allow 
water to go from one aquifer to the other. 

Immobilization: In the context of this report, the application of processes and procedures to retain 
toxic elements, especially selenium, in a given (soil) area. This is done to limit the movement and 
availability of those metal species which may make them environmental hazards. 

Ion exchange: A reversible chemical reaction between a solid (ion exchanger) and a fluid (usually a 
water .solution), by means of which ions may be interchanged from one substance to another. 

Irrigation efficiency: The ratio of the average depth of water infiltrated and stored in the root zone to 
the average depth of water applied to the field. Application efficiency of an irrigation system is 
estimated by dividing the crop water use between irrigations by the amount of water applied during the 
last irrigation. 

Leaching: The dissolution and flushing of salts from the soils by the downward percolation of water. 

Methylation: The chemical attachment of one or more methyl (CH3) groups to an element or 
compound. 



180 



Mitigation: One or all of the following: (a) Avoiding an impact altogether by not taking a certain 
action or parts of an action; (b) minimizing impacts by limiting the degree or magnitude of an action and 
its implementation; (c) rectifying an impact by repairing, rehabilitating, or restoring the affected 
environment; (d) reducing or eliminating an impact over time by preservation and maintenance 
operations during the life of an action; and (e) compensating for an impact by replacing or providing 
substitute resources or environments. 

Oxidation: A chemical reaction taking place by loss of electrons or addition of oxygen. 

Oxidation state: In chemical terms, it is the number of electrons that can be added or subtracted from 
a chemical atom in a combined state to convert it to elemental form. Also known as the oxidation 
number or valence and could be positive or negative. 

Part per billion (ppb): One part by weight per 1 billion (10^) parts. In water, nearly equivalent to 1 
microgram per liter (|i.g/L), or 1 microgram per kilogram (p-g/kg) in solids. 

Part per million (ppm): One part by weight per 1 million (10^) parts. In water, nearly equivalent to 1 
milligram per liter (mg/L), or 1 milligram per kilogram (mg/kg), also 1 microgram per gram (pg/g). 

Percolation: In the context of this report, the downward movement of water through the soil or 
alluvium to the ground-water table. 

Potential problem water: Shallow ground water within 5 feet of the surface of irrigated lands during 
at least part of the year that has chemical characteristics adversely affecting agriculture and, if the 
water were to be drained, fish and wildlife, public health, or attainment of State surface-water quality 
objectives. 

Principal study area: Primarily the western side of the San Joaquin Valley, comprising lands, waters, 
and related resources currently affected by problems related to agricultural drainage, as well as lands 
likely to be affected in the future. 

Problem water: That part of potential problem water that, because of its adverse impact on crops, 
soils, or off-site areas, and water and land uses, requires drainage and associated management. 

Recharge: The processes of water filling the voids in an aquifer, which causes the piezometric head or 
water table to rise in elevation. 

Reduction: A chemical reaction taking place by acceptance of electrons, removal of oxygen, or 
addition of hydrogen. 

Riparian: Pertaining to the banks and other terrestrial environs adjacent to water bodies, watercourses, 
and surface-emergent aquifers (for example, springs, seeps, and oases), whose waters provide soil 
moisture significantly in excess of that otherwise available through local precipitation. Vegetation 
typical of this environment depends on the availability of excess water. 

Root-zone storage: Water present in the first few feet, usually within 5 feet of the ground surface in 
field crops and vegetables; within 10 feet for some fruit and nut trees. 

Salinity: The salt content of dissolved mineral salts in water or soil. Salinity in water is measured by 
determining the amount of total dissolved solids (TDS) or by the electrical conductivity (EC); 
1,000 )j.S/cm is approximately equal to 650 ppm as TDS. 

Salts: In chemistry, the compound formed when the hydrogen of an acid is replaced by a metal or its 
equivalent. Examples are sodium chloride, calcium sulfate, and magnesium carbonate. In this report, it 
generally refers to chemical salts as they are dissolved in water or present in soils. The major 
components of drainage water salts are sodium, sulfate, and chloride. 



181 



Salt balance: The equilibrium established between salts imported to an area and the salts exported 
from the same area. When used in a regional sense, imported salts are those contained in 
surface-applied water and may include other inputs such as fertilizer, soil amendments, and 
precipitation; exported salts arc those conveyed from the area through surface and subsurface flows. 
The term "salt balance" can also be applied to the crop root zone. In this sense, it refers to an 
equilibrium state of soil salinity where there is no net salt accumulation in the root zone. Net 
accumulation of salt in the crop root zone can reduce crop yields. 

Salt load: The total amount of salts contained in a given volume of water entering or leaving an area. 

Seepage: Water escaping from a channel or an impoundment by percolation. 

Selenate: Ionized selenium, usually present as a salt, existing in a valence (or oxidation) state of +6. 
The chemical symbol is Se04"2. 

Selenite: Ionized selenium, usually present as a salt, existing in a valence (or oxidation) state of +4. 
The chemical symbol is Se03"2. 

Semlconfined aquifer: As used in this report, it includes all aquifers above the Corcoran Clay, 
including the so-called uncoiifined aquifer. 

Shallow ground water: Ground water within 20 feet of the land surface. 

Sierran sand: A term referring to a distinct subsurface body of water-bearing material underlying the 
San Joaquin Valley. These deposits originated from the Sierra Nevada. Term is equivalent to "Sierran 
sediment" and "Sierra Nevada sediment." 

Soil sallnization: The accumulation of soluble salts in the soil by the evaporation of water from the 
soil zone. 

Solar ponds: Nonconvective, salt-gradient solar ponds discussed in this report are about 6.5 to 16.5 
feet deep with three distinct water salinity/density zones. Short-wave solar radiation penetrates the 
upper zones into the lower, denser, heat storage zone and raises its temperature. The stored heat can 
be used as a low-temperature energy source. 

Subsidence: A local mass movement that involves principally the gradual downward settling or 
sinking of the earth's surface with little or no horizontal motion. It may be due to natural geologic 
processes or mass activity such as removal of subsurface solids, liquids, or gases, and wetting of some 
types of moisture-deficient loose or porous deposits. 

Substance of concern: One of a group of toxic or potentially toxic chemical elements or constituents 
present in agricultural drainage water. 

Substitute water supply: An adequate nontoxic and reliable freshwater supply equal in volume to the 
agricultural drainage water previously used by wildlife and/or wildlife habitat. In practical application, it 
is water to replace a supply on which biological dependence has developed. 

Subsurface drainage water: Surplus water removed from within the soil by natural or artificial 
means, such as by drains placed below the surface to lower the water table below the root zone. In this 
report, unless otherwise qualified, drainage water refers to subsurface drainage water. 

Tailwater: Irrigation water that flows over an irrigated field without infiltrating the soil. Synonymous 
with "surface drainage water" and "irrigation return flow." 

Tile drain: An on-farm subsurface drain made of flexible plastic pipe (formerly made of clay tile). 

Total dissolved solids: A measure of the amount of dissolved material in a liquid (usually water). It 
is used to determine salinity. The procedure requires measuring (weighing) the amount of solid 
remaining after evaporation of the liquid for a given time period and at a specified temperature. 



182 



Trace elements: Those elements present in the environment at small but measurable concentrations, 
usually less than 1 part per million. 

Transpiration: The passage of water through the stomata of plant leaves into the atmosphere. 

Upland: Generally means a land zone sufficiently above and/or away from freshwater bodies, 
watercourses, and surface-emergent aquifers to be largely dependent on precipitation for its water 
supplies. As used in this report, upland also refers to lands other than those which are seasonally or 
permanently wet. 

Volatilization: The conversion of a chemical substance from a liquid or solid state to the gaseous 
(vapor) state. 

Waterlogged: Soaked or saturated; said of an area affected by a high water table; that is, where water 
stands near, at, or above the land surface. 

Water table: The area in unconfined subsurface material where hydrostatic pressure equals 
atmospheric pressure. Generally, the boundary between the saturated and unsaturated subsurface soil 
zones. 

Wetland: A zone periodically or continuously submerged or having high soil moisture, which has 
aquatic and/or riparian vegetation components, and is maintained by water supplies significantly in 
excess of those otherwise available through local precipitation. 

Wildlife habitat: An area that provides a water supply and vegetative habitat for wildlife. 



183 



GPO: 1990—585-360 



Department of Water Resources 

Travis Latham Editing 

Gayie Dowd Delineation 

Chuck Lano 

Teresa Chaney Design 






P00001928